System Instructions

This prompt is divided into three sections:

System Instructions (this section) — structural orientation only. Do not treat this

section as task input.

Input Context — begins with the heading # Input Context. All blocks are wrapped in

<pblock> tags. Two block types:

File blocks: <pblock filename="<name>" role="<role>" guidance="..."> — optional

guidance attribute carries context-specific instructions; content is in a fenced block.

Metadata/section blocks: <pblock label="<label>" kind="<kind>"> — job parameters,

rules, instructions, or group headers.

Agent Task — begins with the heading # Agent Task. Defines your persona, constraints,

and required outputs. Read all input context before acting on this section.

Input Context

Analysis job

BLUEPRINT_PATH: /mnt/c/Users/barlo/projects/drydock/uat/jq/runs/20260822.044627/workspace/targets/jq/blueprint
DATE: 2026-08-22
COMPASS_EXISTS: true
COMPASS_PENDING_FORMAT: false
DISPLAY_NAME: drydock jq Uat Kit
SHORT_DESCRIPTION: Flagship drydock UAT kit. ~620 conformance test conditions from the upstream jq test suite (46 excluded, reasons in exclusions.txt). Provenance: byte-for-byte upstream files from github.com/jqlang/jq at tag jq-1.8.2, SHA-256 verified in PROVENANCE.md.

</pblock>

# Sea Trials: jq

## Policy

| Consequence | On FAIL | On INCONCLUSIVE |
|---|---|---|
| blocks  | fail   | attest |
| scores  | score  | score  |
| attests | report | report |

## st-001: The supplied scoring script passes
Type: technical
Required: yes
Criterion: The completed interpreter shall make sh sources/full_test.sh exit zero; that script's exit status is the sole acceptance verdict.
Testability: deterministic
Consequence: blocks
Verification: proof
Command: ["sh", "sources/full_test.sh"]
Pattern: ubiquitous

</pblock>

# Rigging Manifest

Compact selection catalog for `drydock analyze` and QuarterDeck. Each entry names a real Rigging
component available for Commander selection. The manifest is selection context only; Analyze does
not open individual component files.

| File | Category | Purpose | Prerequisites |
|---|---|---|---|
| `BRANDING_DOCUMENTATION.md` | Branding | The users voice for Documentation voice, structure, and presentation rules. | — |
| `BRANDING_MAIN.md` | Branding | Core product branding (colors pallette etc ) and visual identity rules. | — |
| `BRANDING_POSTS.md` | Branding | Social and announcement post branding rules. | `BRANDING_MAIN.md` |
| `BRANDING_PROJECT_DOCS.md` | Branding | The users voice, structure, and editing protocol for the authoritative project specification document. | — |
| `BRANDING_WEBSITE.md` | Branding | Website branding, voice, and presentation rules. | `BRANDING_MAIN.md` |
| `BRANDING_WHITEPAPERS.md` | Branding | Whitepaper branding and long-form presentation rules. | `BRANDING_MAIN.md` |
| `alexa-skills-kit.md` | AWS | Alexa Skill kit configuration, interaction models, and intent handling. | `common.md`, `python.md` |
| `aws-api-gateway.md` | AWS | AWS HTTP API Gateway Rules. | `aws-lambda.md` |
| `aws-dynamodb.md` | AWS | AWS DynamoDB single-table catalog and state patterns. | `cloud-client-library.md` |
| `aws-lambda.md` | AWS | AWS Lambda handlers, packaging, IAM, and testing patterns. | `python.md` |
| `aws-s3.md` | AWS | Private encrypted S3 storage and prefix-scoped sharing patterns. | `cloud-client-library.md` |
| `aws-sqs.md` | AWS | SQS durable queue, polling, and error-handling patterns. | `aws-lambda.md` |
| `bootstrap5.md` | Web Server | Bootstrap 5 layout, components, and form conventions. | — |
| `cloud-client-library.md` | AWS | Encapsulated AWS library for use in applications; application dont uses boto3. | `python.md`, `persistence.md` |
| `common.md` | Technologies | Common project layout, scripts, Git hygiene, and development workflow. | — |
| `django.md` | Web Server | Django settings, ORM, migrations, admin, and web application patterns. | `common.md`, `python.md` |
| `env_variables_and_secrets.md` | Technologies | Secret hygiene, environment validation, and `.env` discipline. | `common.md` |
| `fastapi.md` | Web Server | FastAPI routers, dependency injection, templates, and testing patterns. | `common.md`, `python.md` |
| `flask.md` | Web Server | Flask application factory, routes, templates, and error handling. | `common.md`, `python.md` |
| `github-actions.md` | Technologies | GitHub Actions CI/CD with OIDC and lint/test gates. | `terraform.md`, `python.md` |
| `go.md` | Technologies | Go module layout, errors, interfaces, concurrency, testing, and build gates. | `common.md` |
| `persistence.md` | Persistence | Typed boundary for persistent stores and external services. | `common.md` |
| `postgres.md` | Persistence | PostgreSQL schema, pooling, migrations, and indexing patterns. | `python.md`, `persistence.md` |
| `python.md` | Technologies | Python conventions, typing, configuration, testing, and dependencies. | `common.md` |
| `sqlite.md` | Persistence | SQLite connections, migrations, WAL, and typed access patterns. | `python.md`, `persistence.md` |
| `terraform.md` | Technologies | Layered Terraform infrastructure and remote-state patterns. | `aws-dynamodb.md`, `aws-s3.md` |
| `typescript.md` | Technologies | TypeScript strict typing, domain modeling, and boundary validation. | `common.md` |
| `ui-flask.bootstrap-client.md` | Web Server | Focused Flask and Bootstrap screen implementation reference. | `flask.md`, `bootstrap5.md` |
| `uv_ruff.md` | Technologies | uv environments and ruff lint/format workflow. | `python.md` |

</pblock>

Imported source files

</pblock>

Source Inventory

Path	Content kind	Disposition	Reason
`sources/INSTRUCTIONS.md`	markdown	analyzed	readable UTF-8
`sources/builtin.jq`	text	analyzed	readable UTF-8
`sources/exclusions.txt`	text	analyzed	readable UTF-8
`sources/full_test.sh`	code	analyzed	readable UTF-8
`sources/jq-manual.txt`	text	chunked	split into 11 bounded chunks
`sources/jq.test`	text	chunked	split into 5 bounded chunks
`sources/lexer.l`	text	analyzed	readable UTF-8
`sources/parser.y`	text	analyzed	readable UTF-8
`sources/run_conformance.py`	code	analyzed	readable UTF-8

</pblock>

# Build Instructions: A jq Interpreter

## Objective

Build an interpreter for the jq language as described in `sources/jq-manual.txt`.
Correctness is measured by the upstream jq conformance corpus, `sources/jq.test`, taken
verbatim from jq 1.8.2. The goal is to pass every case the corpus supplies, with none
failed and none errored. The suite's size is a property of the pinned corpus; never
assert a case count.

The implementation language is Python, fixed by this Target's `TECHNOLOGY_STACK.md` and
governed by `stack/python.md`.

jq is a small language with a large semantic core. Almost every filter is a **generator**:
it takes one input and produces a stream of zero, one, or many outputs, and downstream
filters run once per upstream output. Backtracking through that stream is not an
optimisation, it is the evaluation model, and `reduce`, `foreach`, `limit`, `first`,
`label`/`break`, and the `?//` destructuring alternative are all defined in terms of it. An
implementation that treats a filter as a function returning one value will pass the early
cases and then stall permanently. Decide the evaluation model before writing builtins.

## Run Harness

`sources/full_test.sh` is the single scoring entry point. It is supplied, not authored: it
is staged verbatim into the build directory alongside the other imported assets, and
`drydock uat` runs `sh sources/full_test.sh` from the completed application root and takes
its exit code and output as the score. It reads:

```sh
#!/bin/sh
# full_test.sh — scoring entry point. Do not filter, skip, or reinterpret.
set -eu
if [ ! -x ./jq ]; then
    echo "error: no executable ./jq at the application root." >&2
    echo "The deliverable is an executable named jq that reads JSON on stdin." >&2
    exit 1
fi
JQ="$PWD/jq" exec python3 sources/run_conformance.py
```

Before relying on any path above, run `ls sources/` in the application directory and
correct the paths in the harness against what is actually on disk. Correcting a path is
the only edit permitted to this script. Do not add flags, filters, skips, or a redirection
of the exit code.

The interface check is deliberately separate from the conformance run so that a missing
program and a genuine conformance failure are distinguishable in the evidence. `JQ` is the
harness's only knowledge of the implementation language; the harness itself is
language-neutral.

## Read-only scoring assets

These four files are the exam. They are hash-verified against the import and restored
before grading, so a modification is reported as tampering rather than honoured:

- `sources/full_test.sh` — the scoring entry point
- `sources/run_conformance.py` — the scoring instrument
- `sources/exclusions.txt` — the declared skips
- `sources/jq.test` — the conformance corpus

Do not write to them. Build `./jq` so that the supplied entry point succeeds; changing the
entry point is not a repair, and a repair pass spent editing one of these files is wasted.

## Interface contract

The program is a filter: an executable file named `jq` at the application root, invoked as

```
./jq -c '<program>'
```

with JSON on **stdin**. It writes each value the program produces to **stdout** as one
compact JSON value per line, and exits `0`.

`-c` is the only option exercised. The program need not implement any other jq
command-line option, and the manual's "Invoking jq" section is omitted from
`sources/jq-manual.txt` for that reason.

Exit codes follow jq's own, and the distinction is load-bearing because the harness grades
on it:

| Exit | Meaning |
|---|---|
| `0` | the program compiled and ran to completion |
| `3` | the program did not compile — a syntax or static error |
| `5` | the program compiled but raised at run time |

A case may legitimately emit several values and then raise; the harness compares the values
produced before the raise, so exit `5` is not by itself a failure. Exit `3` on a valid
program is always a failure. Diagnostics go to **stderr** and are never compared.

Any implementation shape that satisfies this contract is acceptable. A
`#!/usr/bin/env python3` script named `jq` that imports the real work from a package
alongside it is the obvious one; `main` should parse arguments and delegate.

## Test / verification process

The imported source files are placed in a `sources/` subdirectory of the application
directory. The only tools required are `python3` and a POSIX `sh`, both already present.
No installation step, no package download, and no network access are required at any
point.

```bash
JQ="$PWD/jq" python3 sources/run_conformance.py                     # the scored run
JQ="$PWD/jq" python3 sources/run_conformance.py -v                  # list passing cases too
JQ="$PWD/jq" python3 sources/run_conformance.py --json              # machine-readable
JQ="$PWD/jq" python3 sources/run_conformance.py --list              # print cases, run nothing
JQ="$PWD/jq" python3 sources/run_conformance.py --select 'reduce'   # one construct at a time
JQ="$PWD/jq" python3 sources/run_conformance.py --select 'reduce' --list   # size that slice
```

During development, `sh sources/full_test.sh` does the interface check and the conformance
run together, and is the same command the score is taken from.

`--select` takes a regular expression matched against the case's program text. It is how
an intermediate story runs its own slice of the corpus, and it is required, not optional.

The harness's own `--help` text for `--select` calls it a development aid and states that
the acceptance gate always runs the whole corpus. That text predates this rule and does not
govern. It is part of a read-only scoring asset and cannot be corrected in place, so it is
corrected here: where the harness's help text and this document disagree, this document is
authoritative.

**Exactly one acceptance check runs the whole corpus.** One terminal story — the last one —
runs `sh sources/full_test.sh`, asserts only `result.returncode == 0`, prints the captured
stdout and stderr so a failure can be diagnosed from the evidence, and carries the Sea
Trial. No other acceptance check may run the corpus unscoped, and none may invoke
`full_test.sh` at all. A partial implementation fails most of the corpus by construction,
so an unscoped mid-build run reports the schedule rather than a defect, and it is slow in
exact proportion to how incomplete the code is.

**Every other story runs its own slice, and the slice executes cases.** Each story's
acceptance invokes `sources/run_conformance.py` with a `--select` expression scoped to the
construct that story implements, supplies `JQ`, and asserts `result.returncode == 0`. Those
are exactly the cases the story's code is supposed to pass, so the run is neither slow nor
red by construction, and the corpus goes green in the order the plan builds it.

`--list` prints the matching cases and runs nothing. Use it while planning, to size and
inspect a selector before committing to it. An acceptance check that invokes it executes
nothing, passes before the story's code exists, and steers no repair; such a check is a
defect. The one exception is the story whose only obligation is that the corpus parses, the
exclusion list applies, and the harness starts — it implements none of the behaviour under
test, so listing is the correct thing for it to assert.

A selector matching no case is a defect too: it buys the story no coverage and reports
success. Check the count with `--list` while planning and widen the expression until it
covers the story's construct. Together the slices cover the corpus; a case no slice reaches
is first executed by the terminal gate, where a failure arrives with the whole build
already spent and no story to attribute it to.

No acceptance check may assert that an imported or staged file merely exists — a
file-presence check is not acceptance.

The summary line is:

```
jq conformance: NNN passed, N failed, N errored, N skipped (corpus jq.test @ jq-1.8.2)
```

The harness reserves exit `2` for its own faults — a missing corpus, an unset `JQ`, a
stale exclusion. Exit `2` never means the interpreter is wrong.

## The corpus format

`sources/jq.test` documents its own format in its header. Cases are separated by blank
lines; blank lines and `#` lines are ignored. A case is a program line, an input line, and
then the expected output values, one per line. A case preceded by `%%FAIL` is a program
that must be **rejected at compile time**: the following lines are upstream jq's
diagnostic, which this harness records but never compares. Reproducing jq's exact error
text is reverse-engineering a C implementation, not conforming to a specification, so a
`%%FAIL` case passes on exit `3` alone.

Values are compared structurally, not textually. `1` and `1.0` are the same jq value; so
are two objects whose keys are printed in a different order. Formatting of output is
therefore not under test, but the **number and order** of values is.

## Declared exclusions

`sources/exclusions.txt` names the corpus cases this kit cannot run, with the reason. They
are the module-loader cases: `import` and `include` resolved against a search path of
fixture files that this kit's flat source import cannot carry. They are reported as
`skipped` and are not part of the score.

The module *grammar* cases are **not** excluded and must pass. `module (.+1); 0`,
`module []; 0`, `include "a" (.+1); 0`, `include "a" []; 0`, `include "\ "; 0`,
`include "\(a)"; 0`, and `%::wat` are all `%%FAIL` cases: the front end must parse the
module syntax far enough to reject them, without ever touching the filesystem.

## Source Roles

Record this table in the Analysis so every asset is staged onto disk in the build
directory. `sources/jq-manual.txt`, `sources/jq.test`, `sources/parser.y`, and
`sources/lexer.l` are large and must be readable from disk during implementation rather
than carried in prompt text.

| Source | Role | Plan disposition | Build disposition |
|---|---|---|---|
| `jq-manual.txt` | normative specification | context | stage |
| `jq.test` | conformance test suite | context | stage |
| `parser.y` | normative specification | context | stage |
| `lexer.l` | normative specification | context | stage |
| `builtin.jq` | reference implementation | context | stage |
| `run_conformance.py` | conformance harness | context | stage |
| `full_test.sh` | conformance harness | context | stage |
| `exclusions.txt` | conformance harness | context | stage |
| `INSTRUCTIONS.md` | author intent | context | prompt-only |

What each staged file is for:

- `sources/jq-manual.txt` — the jq language manual at 1.8.2, rendered to plain text. The
  primary specification, and the normative description of every builtin.
- `sources/jq.test` — the conformance corpus. Also the most precise available statement of
  the semantics, especially for generators and backtracking.
- `sources/parser.y` — upstream's yacc grammar. The authority on operator precedence,
  associativity, and the shape of every syntactic form.
- `sources/lexer.l` — upstream's lexer. The authority on tokens, string interpolation, and
  escape handling.
- `sources/builtin.jq` — the subset of jq's builtins that upstream defines in jq itself.
  Read it as a specification of those builtins' semantics.
- `sources/run_conformance.py`, `sources/full_test.sh`, `sources/exclusions.txt` — the
  scoring instruments, read-only as stated above.

## Suggested implementation order

The difficulty is concentrated in one place — the evaluation model — and not spread evenly
across the corpus. Build the core correctly before reaching for coverage.

1. **Lexer and parser.** Follow `sources/lexer.l` and `sources/parser.y` directly. Produce
   an AST. Precedence, `?` suffixes, string interpolation, and the `def` forms are all
   settled there. Reject invalid programs with exit `3`.
2. **The generator core.** Evaluate a filter as something that yields a stream of values:

</pblock>

   `.`, literals, `|`, `,`, field access, iteration, arithmetic, comparison, and
   `empty`. Every later feature is expressed in terms of this. Get `[.[] | f]`,
   cartesian products over multi-output arguments, and short-circuiting right.
3. **Paths and assignment.** `path(f)`, `getpath`, `setpath`, `delpaths`, `del`, and then
   `=`, `|=`, `+=`, and friends. Assignment is defined over path expressions, so this
   cannot precede step 2.
4. **Control flow.** `if`/`then`/`elif`/`else`/`end`, `try`/`catch` and `?`, `//`,
   `reduce`, `foreach`, `label`/`break`, `limit`, `first`, `last`, `until`, `while`,
   `recurse`. This is where backtracking is tested hardest.
5. **Functions, variables, and destructuring.** `def` with arity and closures, `as`
   bindings, object and array patterns, and the `?//` alternative operator.
6. **Builtins.** Work outward from `sources/builtin.jq` and the manual: strings, arrays,
   objects, `sort_by`/`group_by`/`unique_by`, `@base64`/`@uri`/`@csv`/`@tsv`/`@sh`
   formats, the date functions, `tostream`, `input`/`inputs`, `$__loc__`, `debug`.
7. **Numbers and edge cases.** `nan`, `infinite`, integer/float equality, large literals,
   and the `have_decnum` builtin — return `false` from it and the corpus takes its
   non-decNumber branch, which native floats satisfy.

The manual is normative and the corpus is precise. Follow both directly rather than
inferring behaviour from jq's printed output.

## Definition of Done

- `sh sources/full_test.sh` runs cleanly with zero errors and exits zero.
- The program satisfies the `./jq -c` → stdin → one-JSON-value-per-line → exit-code
  contract.
- Every corpus case that runs passes: the failed and errored counts are both zero, and the
  skipped count matches the declared exclusions. The harness exit status is the verdict and
  the whole verdict — assert `returncode == 0` and stop there. Do not assert on the text of
  the summary line at all: the case totals belong to the pinned corpus, and a check that
  reads a runner's printed output is measuring the runner rather than the interpreter.
- Do not create acceptance checks asserting that imported or staged files merely exist.
- The interpreter is written from the specification. **Every third-party jq
  implementation or binding is forbidden** — `jq.py`, `pyjq`, `jqlang`, `gojq`, `jaq`, and
  any other — as is shelling out to a system `jq` binary. A wrapper around real jq scores
  perfectly and makes the exercise meaningless.
- The project declares no third-party runtime dependency. The standard library is
  sufficient: `json`, `decimal`, `math`, `re`, `datetime`, `time`, `base64`, `unicodedata`,
  `itertools`, `functools`, `dataclasses`, `argparse`, `sys`.
- No network access at any point, including at test time. No package is installed, and no
  tool beyond `python3` and POSIX `sh` is invoked.
- Deliver a concise project `README.md` documenting the stdin/stdout interface, the exit
  codes, and the `sh sources/full_test.sh` command.

</pblock>

def halt_error: halt_error(5);
def error(msg): msg|error;
def map(f): [.[] | f];
def select(f): if f then . else empty end;
def sort_by(f): _sort_by_impl(map([f]));
def group_by(f): _group_by_impl(map([f]));
def unique_by(f): _unique_by_impl(map([f]));
def max_by(f): _max_by_impl(map([f]));
def min_by(f): _min_by_impl(map([f]));
def add(f): reduce f as $x (null; . + $x);
def add: add(.[]);
def del(f): delpaths([path(f)]);
def abs: if . < 0 then - . else . end;
def _assign(paths; $value): reduce path(paths) as $p (.; setpath($p; $value));
def _modify(paths; update):
    reduce path(paths) as $p ([., []];
        . as $dot
      | null
      | label $out
      | ($dot[0] | getpath($p)) as $v
      | (
          (   $$$$v
            | update
            | (., break $out) as $v
            | $$$$dot
            | setpath([0] + $p; $v)
          ),
          (
              $$$$dot
            | setpath([1, (.[1] | length)]; $p)
          )
        )
    ) | . as $dot | $dot[0] | delpaths($dot[1]);
def map_values(f): .[] |= f;

# recurse
def recurse(f): def r: ., (f | r); r;
def recurse(f; cond): def r: ., (f | select(cond) | r); r;
def recurse: recurse(.[]?);

def to_entries: [keys_unsorted[] as $k | {key: $k, value: .[$k]}];
def from_entries: map({ (.key // .Key // .name // .Name):
  if has("value") then .value else .Value end }) | add // {};
def with_entries(f): to_entries | map(f) | from_entries;
def reverse: [.[length - 1 - range(0;length)]];
def indices($i): if type == "array" and ($i|type) == "array" then .[$i]
  elif type == "array" then .[[$i]]
  elif type == "string" and ($i|type) == "string" then _strindices($i)
  else .[$i] end;
def index($i):   indices($i) | .[0];       # TODO: optimize
def rindex($i):  indices($i) | .[-1:][0];  # TODO: optimize
def paths: path(recurse)|select(length > 0);
def paths(node_filter): path(recurse|select(node_filter))|select(length > 0);
def isfinite: type == "number" and (isinfinite | not);
def arrays: select(type == "array");
def objects: select(type == "object");
def iterables: select(type|. == "array" or . == "object");
def booleans: select(type == "boolean");
def numbers: select(type == "number");
def normals: select(isnormal);
def finites: select(isfinite);
def strings: select(type == "string");
def nulls: select(. == null);
def values: select(. != null);
def scalars: select(type|. != "array" and . != "object");
def join($x): reduce .[] as $i (null;
            (if .==null then "" else .+$x end) +
            ($i | if type=="boolean" or type=="number" then tostring else .//"" end)
        ) // "";
def _flatten($x): reduce .[] as $i ([]; if $i | type == "array" and $x != 0 then . + ($i | _flatten($x-1)) else . + [$i] end);
def flatten($x): if $x < 0 then error("flatten depth must not be negative") else _flatten($x) end;
def flatten: _flatten(-1);
def range($x): range(0;$x);
def fromdateiso8601: strptime("%Y-%m-%dT%H:%M:%SZ")|mktime;
def todateiso8601: strftime("%Y-%m-%dT%H:%M:%SZ");
def fromdate: fromdateiso8601;
def todate: todateiso8601;
def ltrimstr($left): if startswith($left) then .[$left | length:] end;
def rtrimstr($right): if endswith($right) then .[:length - ($right | length)] end;
def trimstr($val): ltrimstr($val) | rtrimstr($val);
def match(re; mode): _match_impl(re; mode; false)|.[];
def match($val): ($val|type) as $vt | if $vt == "string" then match($val; null)
   elif $vt == "array" and ($val | length) > 1 then match($val[0]; $val[1])
   elif $vt == "array" and ($val | length) > 0 then match($val[0]; null)
   else error( $vt + " not a string or array") end;
def test(re; mode): _match_impl(re; mode; true);
def test($val): ($val|type) as $vt | if $vt == "string" then test($val; null)
   elif $vt == "array" and ($val | length) > 1 then test($val[0]; $val[1])
   elif $vt == "array" and ($val | length) > 0 then test($val[0]; null)
   else error( $vt + " not a string or array") end;
def capture(re; mods): match(re; mods) | reduce ( .captures | .[] | select(.name != null) | { (.name) : .string } ) as $pair ({}; . + $pair);
def capture($val): ($val|type) as $vt | if $vt == "string" then capture($val; null)
   elif $vt == "array" and ($val | length) > 1 then capture($val[0]; $val[1])
   elif $vt == "array" and ($val | length) > 0 then capture($val[0]; null)
   else error( $vt + " not a string or array") end;
def scan($re; $flags):
  match($re; "g" + $flags)
    | if (.captures|length > 0)
      then [ .captures | .[] | .string ]
      else .string
      end;
def scan($re): scan($re; null);

# splits/1 produces a stream; split/1 is retained for backward compatibility.
def splits($re; $flags):
  .[foreach (match($re; $flags+"g"), null) as {$offset, $length}
      (null; {start: .next, end: $offset, next: ($offset+$length)})];
def splits($re): splits($re; null);

# split emits an array for backward compatibility
def split($re; $flags): [ splits($re; $flags) ];

# If s contains capture variables, then create a capture object and pipe it to s, bearing
# in mind that s could be a stream
def sub($re; s; $flags):
   . as $in
   | (reduce match($re; $flags) as $edit
        ({result: [], previous: 0};
            $in[ .previous: ($edit | .offset) ] as $gap
            # create the "capture" objects (one per item in s)
            | [reduce ( $edit | .captures | .[] | select(.name != null) | { (.name) : .string } ) as $pair
                 ({}; . + $pair) | s ] as $inserts
            | reduce range(0; $inserts|length) as $ix (.; .result[$ix] += $gap + $inserts[$ix])
            | .previous = ($edit | .offset + .length ) )
          | .result[] + $in[.previous:] )
      // $in;

def sub($re; s): sub($re; s; "");

def gsub($re; s; flags): sub($re; s; flags + "g");
def gsub($re; s): sub($re; s; "g");

########################################################################
# generic iterator/generator
def while(cond; update):
     def _while:
         if cond then ., (update | _while) else empty end;
     _while;
def until(cond; next):
     def _until:
         if cond then . else (next|_until) end;
     _until;
def limit($n; expr):
  if $n > 0 then label $out | foreach expr as $item ($n; . - 1; $item, if . <= 0 then break $out else empty end)
  elif $n == 0 then empty
  else error("limit doesn't support negative count") end;
def skip($n; expr):
  if $n > 0 then foreach expr as $item ($n; . - 1; if . < 0 then $item else empty end)
  elif $n == 0 then expr
  else error("skip doesn't support negative count") end;
# range/3, with a `by` expression argument
def range($init; $upto; $by):
    if $by > 0 then $init|while(. < $upto; . + $by)
  elif $by < 0 then $init|while(. > $upto; . + $by)
  else empty end;
def first(g): label $out | g | ., break $out;
def isempty(g): first((g|false), true);
def all(generator; condition): isempty(generator|condition and empty);
def any(generator; condition): isempty(generator|condition or empty)|not;
def all(condition): all(.[]; condition);
def any(condition): any(.[]; condition);
def all: all(.[]; .);
def any: any(.[]; .);
def nth($n; g):
  if $n < 0 then error("nth doesn't support negative indices")
  else first(skip($n; g)) end;
def first: .[0];
def last: .[-1];
def nth($n): .[$n];
def combinations:
    if length == 0 then [] else
        .[0][] as $x
          | (.[1:] | combinations) as $y
          | [$x] + $y
    end;
def combinations(n):
    . as $dot
      | [range(n) | $dot]
      | combinations;
# transpose a possibly jagged matrix, quickly;
# rows are padded with nulls so the result is always rectangular.
def transpose: [range(0; map(length)|max // 0) as $i | [.[][$i]]];
def in(xs): . as $x | xs | has($x);
def inside(xs): . as $x | xs | contains($x);
def repeat(exp):
     def _repeat:
         exp, _repeat;
     _repeat;
def inputs: try repeat(input) catch if .=="break" then empty else error end;
# like ruby's downcase - only characters A to Z are affected
def ascii_downcase:
  explode | map( if 65 <= . and . <= 90 then . + 32  else . end) | implode;
# like ruby's upcase - only characters a to z are affected
def ascii_upcase:
  explode | map( if 97 <= . and . <= 122 then . - 32  else . end) | implode;

# Streaming utilities
def truncate_stream(stream):
  . as $n | null | stream | . as $input | if (.[0]|length) > $n then setpath([0];$input[0][$n:]) else empty end;
def fromstream(i): {x: null, e: false} as $init |
  # .x = object being built; .e = emit and reset state
  foreach i as $i ($init
  ; if .e then $init else . end
  | if $i|length == 2
    then setpath(["e"]; $i[0]|length==0) | setpath(["x"]+$i[0]; $i[1])
    else setpath(["e"]; $i[0]|length==1) end
  ; if .e then .x else empty end);
def tostream:
  path(def r: (.[]?|r), .; r) as $p |
  getpath($p) |
  reduce path(.[]?) as $q ([$p, .]; [$p+$q]);

# Apply f to composite entities recursively, and to atoms
def walk(f):
  def w:
    if type == "object"
    then map_values(w)
    elif type == "array" then map(w)
    else .
    end
    | f;
  w;

# pathexps could be a stream of dot-paths
def pick(pathexps):
  . as $in
  | reduce path(pathexps) as $a (null;
      setpath($a; $in|getpath($a)) );

# ensure the output of debug(m1,m2) is kept together:
def debug(msgs): (msgs | debug | empty), .;

# SQL-ish operators here:
def INDEX(stream; idx_expr):
  reduce stream as $row ({}; .[$row|idx_expr|tostring] = $row);
def INDEX(idx_expr): INDEX(.[]; idx_expr);
def JOIN($idx; idx_expr):
  [.[] | [., $idx[idx_expr]]];
def JOIN($idx; stream; idx_expr):
  stream | [., $idx[idx_expr]];
def JOIN($idx; stream; idx_expr; join_expr):
  stream | [., $idx[idx_expr]] | join_expr;
def IN(s): any(s == .; .);
def IN(src; s): any(src == s; .);

</pblock>

# exclusions.txt — corpus cases this kit cannot run, and why.
#
# The corpus in sources/jq.test is byte-for-byte upstream and is never edited. Where a case
# cannot run under this kit's harness, it is named here instead, so every skip is visible,
# reasoned, and auditable against the upstream file. This file is a scoring asset: it is
# hash-verified against the import and restored before grading.
#
# One verbatim program line per entry. An entry that matches no case in the corpus is a hard
# error (exit 2), not a shrug — a silent no-op would quietly re-admit a case the kit cannot run
# if the corpus pin ever moved.
#
# Nothing is excluded for being hard. The module-loader cases below are excluded because the
# kit physically cannot deliver their inputs, not because the semantics are difficult.

# --------------------------------------------------------------------------------------------
# Module loading from disk.
#
# These cases resolve `import` and `include` against a module search path supplied by jq's -L
# flag, reading roughly twenty fixture files spread across nested directories upstream
# (tests/modules/{b,c,lib/jq/e,home2/.jq,...}). Drydock copies a kit's declared sources into the
# application flattened by basename, so that directory tree cannot be carried, and the interface
# this kit fixes exercises no flag but -c.
#
# Only the loader cases are excluded. The module *grammar* cases — `module (.+1); 0`,
# `module []; 0`, `include "a" (.+1); 0`, `include "a" []; 0`, `include "\ "; 0`,
# `include "\(a)"; 0`, and `%::wat` — remain in the scored set: they are parse errors that a
# correct front end rejects without ever touching the filesystem.
# --------------------------------------------------------------------------------------------

import "a" as foo; import "b" as bar; def fooa: foo::a; [fooa, bar::a, bar::b, foo::a]
import "c" as foo; [foo::a, foo::c]
include "c"; [a, c]
import "data" as $e; import "data" as $d; [$d[].this,$e[].that,$d::d[].this,$e::e[].that]|join(";")
import "data" as $a; import "data" as $b; def f: {$a, $b}; f
include "shadow1"; e
include "shadow1"; include "shadow2"; e
import "shadow1" as f; import "shadow2" as f; import "shadow1" as e; [e::e, f::e]
import "syntaxerror" as e; .
import "test_bind_order" as check; check::check

# `modulemeta` reports a module's declared dependencies and definitions. Its three cases take
# the module name "c" as input and read tests/modules/c/c.jq from the search path, so they fail
# for the same reason as the loader cases above.
modulemeta
modulemeta | .deps | length
modulemeta | .defs | length

</pblock>

#!/bin/sh
# full_test.sh — scoring entry point. Do not filter, skip, or reinterpret.
#
# `drydock uat` runs `sh sources/full_test.sh` from the completed application root and takes its
# exit code and output as the score. The interface check is separate from the conformance run so
# that a missing or non-executable program and a genuine conformance failure are distinguishable
# in the evidence. JQ is the harness's only knowledge of the implementation language; the
# harness itself is language-neutral.
set -eu
if [ ! -x ./jq ]; then
    echo "error: no executable ./jq at the application root." >&2
    echo "The deliverable is an executable named jq that reads JSON on stdin." >&2
    exit 1
fi
JQ="$PWD/jq" exec python3 sources/run_conformance.py

</pblock>

The jq Language Manual
======================

Rendered from the jq manual at tag jq-1.8.2 (docs/content/manual/v1.8/manual.yml).
See PROVENANCE.md for the upstream hash.

This is the normative description of the jq language and is the primary specification
for this project. Section and entry titles, prose, and worked examples are upstream's,
verbatim and in document order. The manual's "Invoking jq" and "Colors" sections are
omitted: they describe jq's command-line option surface, which this project does not
implement and the conformance corpus does not exercise.

Worked examples read:

    Example: <the jq program>
      Input: <the JSON input>
     Output: <each JSON value the program produces, one per line>


Introduction
------------

A jq program is a "filter": it takes an input, and produces an
output. There are a lot of builtin filters for extracting a
particular field of an object, or converting a number to a string,
or various other standard tasks.

Filters can be combined in various ways - you can pipe the output of
one filter into another filter, or collect the output of a filter
into an array.

Some filters produce multiple results, for instance there's one that
produces all the elements of its input array. Piping that filter
into a second runs the second filter for each element of the
array. Generally, things that would be done with loops and iteration
in other languages are just done by gluing filters together in jq.

It's important to remember that every filter has an input and an
output. Even literals like "hello" or 42 are filters - they take an
input but always produce the same literal as output. Operations that
combine two filters, like addition, generally feed the same input to
both and combine the results. So, you can implement an averaging
filter as `add / length` - feeding the input array both to the `add`
filter and the `length` filter and then performing the division.

But that's getting ahead of ourselves. :) Let's start with something
simpler:



============================================================================
SECTION: Basic filters
============================================================================


----------------------------------------------------------------------------
Identity: `.`
----------------------------------------------------------------------------

The absolute simplest filter is `.` .  This filter takes its
input and produces the same value as output.  That is, this
is the identity operator.

Since jq by default pretty-prints all output, a trivial
program consisting of nothing but `.` can be used to format
JSON output from, say, `curl`.

Although the identity filter never modifies the value of its
input, jq processing can sometimes make it appear as though
it does.  For example, using the current implementation of
jq, we would see that the expression:

    1E1234567890 | .

produces `1.7976931348623157e+308` on at least one platform.
This is because, in the process of parsing the number, this
particular version of jq has converted it to an IEEE754
double-precision representation, losing precision.

The way in which jq handles numbers has changed over time
and further changes are likely within the parameters set by
the relevant JSON standards.  Moreover, build configuration
options can alter how jq processes numbers.

The following remarks are therefore offered with the
understanding that they are intended to be descriptive of the
current version of jq and should not be interpreted as being
prescriptive:

(1) Any arithmetic operation on a number that has not
already been converted to an IEEE754 double precision
representation will trigger a conversion to the IEEE754
representation.

(2) jq will attempt to maintain the original decimal
precision of number literals (if the `--disable-decnum`
build configuration option was not used), but in expressions
such `1E1234567890`, precision will be lost if the exponent
is too large.

(3) Comparisons are carried out using the untruncated
big decimal representation of numbers if available, as
illustrated in one of the following examples.

The examples below use the builtin function `have_decnum` in
order to demonstrate the expected effects of using / not
using the `--disable-decnum` build configuration option, and
also to allow automated tests derived from these examples to
pass regardless of whether that option is used.

    Example: .
      Input: "Hello, world!"
     Output: "Hello, world!"

    Example: .
      Input: 0.12345678901234567890123456789
     Output: 0.12345678901234567890123456789

    Example: [., tojson] == if have_decnum then [12345678909876543212345,"12345678909876543212345"] else [12345678909876543000000,"12345678909876543000000"] end
      Input: 12345678909876543212345
     Output: true

    Example: [1234567890987654321,-1234567890987654321 | tojson] == if have_decnum then ["1234567890987654321","-1234567890987654321"] else ["1234567890987654400","-1234567890987654400"] end
      Input: null
     Output: true

    Example: . < 0.12345678901234567890123456788
      Input: 0.12345678901234567890123456789
     Output: false

    Example: map([., . == 1]) | tojson == if have_decnum then "[[1,true],[1.000,true],[1.0,true],[1.00,true]]" else "[[1,true],[1,true],[1,true],[1,true]]" end
      Input: [1, 1.000, 1.0, 100e-2]
     Output: true

    Example: . as $big | [$big, $big + 1] | map(. > 10000000000000000000000000000000) | . == if have_decnum then [true, false] else [false, false] end
      Input: 10000000000000000000000000000001
     Output: true


----------------------------------------------------------------------------
Object Identifier-Index: `.foo`, `.foo.bar`
----------------------------------------------------------------------------

The simplest *useful* filter has the form `.foo`. When given a
JSON object (aka dictionary or hash) as input, `.foo` produces
the value at the key "foo" if the key is present, or null otherwise.

A filter of the form `.foo.bar` is equivalent to `.foo | .bar`.

The `.foo` syntax only works for simple, identifier-like keys, that
is, keys that are all made of alphanumeric characters and
underscore, and which do not start with a digit.

If the key contains special characters or starts with a digit,
you need to surround it with double quotes like this:
`."foo$"`, or else `.["foo$"]`.

For example `.["foo::bar"]` and `.["foo.bar"]` work while
`.foo::bar` does not.

    Example: .foo
      Input: {"foo": 42, "bar": "less interesting data"}
     Output: 42

    Example: .foo
      Input: {"notfoo": true, "alsonotfoo": false}
     Output: null

    Example: .["foo"]
      Input: {"foo": 42}
     Output: 42


----------------------------------------------------------------------------
Optional Object Identifier-Index: `.foo?`
----------------------------------------------------------------------------

Just like `.foo`, but does not output an error when `.` is not an
object.

    Example: .foo?
      Input: {"foo": 42, "bar": "less interesting data"}
     Output: 42

    Example: .foo?
      Input: {"notfoo": true, "alsonotfoo": false}
     Output: null

    Example: .["foo"]?
      Input: {"foo": 42}
     Output: 42

    Example: [.foo?]
      Input: [1,2]
     Output: []


----------------------------------------------------------------------------
Object Index: `.[<string>]`
----------------------------------------------------------------------------

You can also look up fields of an object using syntax like
`.["foo"]` (`.foo` above is a shorthand version of this, but
only for identifier-like strings).


----------------------------------------------------------------------------
Array Index: `.[<number>]`
----------------------------------------------------------------------------

When the index value is an integer, `.[<number>]` can index
arrays.  Arrays are zero-based, so `.[2]` returns the third
element.

Negative indices are allowed, with -1 referring to the last
element, -2 referring to the next to last element, and so on.

    Example: .[0]
      Input: [{"name":"JSON", "good":true}, {"name":"XML", "good":false}]
     Output: {"name":"JSON", "good":true}

    Example: .[2]
      Input: [{"name":"JSON", "good":true}, {"name":"XML", "good":false}]
     Output: null

    Example: .[-2]
      Input: [1,2,3]
     Output: 2


----------------------------------------------------------------------------
Array/String Slice: `.[<number>:<number>]`
----------------------------------------------------------------------------

The `.[<number>:<number>]` syntax can be used to return a
subarray of an array or substring of a string. The array
returned by `.[10:15]` will be of length 5, containing the
elements from index 10 (inclusive) to index 15 (exclusive).
Either index may be negative (in which case it counts
backwards from the end of the array), or omitted (in which
case it refers to the start or end of the array).
Indices are zero-based.

    Example: .[2:4]
      Input: ["a","b","c","d","e"]
     Output: ["c", "d"]

    Example: .[2:4]
      Input: "abcdefghi"
     Output: "cd"

    Example: .[:3]
      Input: ["a","b","c","d","e"]
     Output: ["a", "b", "c"]

    Example: .[-2:]
      Input: ["a","b","c","d","e"]
     Output: ["d", "e"]


----------------------------------------------------------------------------
Array/Object Value Iterator: `.[]`
----------------------------------------------------------------------------

If you use the `.[index]` syntax, but omit the index
entirely, it will return *all* of the elements of an
array. Running `.[]` with the input `[1,2,3]` will produce the
numbers as three separate results, rather than as a single
array. A filter of the form `.foo[]` is equivalent to
`.foo | .[]`.

You can also use this on an object, and it will return all
the values of the object.

Note that the iterator operator is a generator of values.

    Example: .[]
      Input: [{"name":"JSON", "good":true}, {"name":"XML", "good":false}]
     Output: {"name":"JSON", "good":true}
             {"name":"XML", "good":false}

    Example: .[]
      Input: []
     Output: (no output)

    Example: .foo[]
      Input: {"foo":[1,2,3]}
     Output: 1
             2
             3

    Example: .[]
      Input: {"a": 1, "b": 1}
     Output: 1
             1


----------------------------------------------------------------------------
`.[]?`
----------------------------------------------------------------------------

Like `.[]`, but no errors will be output if . is not an array
or object. A filter of the form `.foo[]?` is equivalent to
`.foo | .[]?`.


----------------------------------------------------------------------------
Comma: `,`
----------------------------------------------------------------------------

If two filters are separated by a comma, then the
same input will be fed into both and the two filters' output
value streams will be concatenated in order: first, all of the
outputs produced by the left expression, and then all of the
outputs produced by the right. For instance, filter `.foo,
.bar`, produces both the "foo" fields and "bar" fields as
separate outputs.

The `,` operator is one way to construct generators.

    Example: .foo, .bar
      Input: {"foo": 42, "bar": "something else", "baz": true}
     Output: 42
             "something else"

    Example: .user, .projects[]
      Input: {"user":"stedolan", "projects": ["jq", "wikiflow"]}
     Output: "stedolan"
             "jq"
             "wikiflow"

    Example: .[4,2]
      Input: ["a","b","c","d","e"]
     Output: "e"
             "c"


----------------------------------------------------------------------------
Pipe: `|`
----------------------------------------------------------------------------

The | operator combines two filters by feeding the output(s) of
the one on the left into the input of the one on the right. It's
similar to the Unix shell's pipe, if you're used to that.

</pblock>

If the one on the left produces multiple results, the one on
the right will be run for each of those results. So, the
expression `.[] | .foo` retrieves the "foo" field of each
element of the input array.  This is a cartesian product,
which can be surprising.

Note that `.a.b.c` is the same as `.a | .b | .c`.

Note too that `.` is the input value at the particular stage
in a "pipeline", specifically: where the `.` expression appears.
Thus `.a | . | .b` is the same as `.a.b`, as the `.` in the
middle refers to whatever value `.a` produced.

    Example: .[] | .name
      Input: [{"name":"JSON", "good":true}, {"name":"XML", "good":false}]
     Output: "JSON"
             "XML"


----------------------------------------------------------------------------
Parenthesis
----------------------------------------------------------------------------

Parenthesis work as a grouping operator just as in any typical
programming language.

    Example: (. + 2) * 5
      Input: 1
     Output: 15



============================================================================
SECTION: Types and Values
============================================================================

jq supports the same set of datatypes as JSON - numbers,
strings, booleans, arrays, objects (which in JSON-speak are
hashes with only string keys), and "null".

Booleans, null, strings and numbers are written the same way as
in JSON. Just like everything else in jq, these simple
values take an input and produce an output - `42` is a valid jq
expression that takes an input, ignores it, and returns 42
instead.

Numbers in jq are internally represented by their IEEE754 double
precision approximation. Any arithmetic operation with numbers,
whether they are literals or results of previous filters, will
produce a double precision floating point result.

However, when parsing a literal jq will store the original literal
string. If no mutation is applied to this value then it will make
to the output in its original form, even if conversion to double
would result in a loss.


----------------------------------------------------------------------------
Array construction: `[]`
----------------------------------------------------------------------------

As in JSON, `[]` is used to construct arrays, as in
`[1,2,3]`. The elements of the arrays can be any jq
expression, including a pipeline. All of the results produced
by all of the expressions are collected into one big array.
You can use it to construct an array out of a known quantity
of values (as in `[.foo, .bar, .baz]`) or to "collect" all the
results of a filter into an array (as in `[.items[].name]`)

Once you understand the "," operator, you can look at jq's array
syntax in a different light: the expression `[1,2,3]` is not using a
built-in syntax for comma-separated arrays, but is instead applying
the `[]` operator (collect results) to the expression 1,2,3 (which
produces three different results).

If you have a filter `X` that produces four results,
then the expression `[X]` will produce a single result, an
array of four elements.

    Example: [.user, .projects[]]
      Input: {"user":"stedolan", "projects": ["jq", "wikiflow"]}
     Output: ["stedolan", "jq", "wikiflow"]

    Example: [ .[] | . * 2]
      Input: [1, 2, 3]
     Output: [2, 4, 6]


----------------------------------------------------------------------------
Object Construction: `{}`
----------------------------------------------------------------------------

Like JSON, `{}` is for constructing objects (aka
dictionaries or hashes), as in: `{"a": 42, "b": 17}`.

If the keys are "identifier-like", then the quotes can be left
off, as in `{a:42, b:17}`.  Variable references as key
expressions use the value of the variable as the key.  Key
expressions other than constant literals, identifiers, or
variable references, need to be parenthesized, e.g.,
`{("a"+"b"):59}`.

The value can be any expression (although you may need to wrap
it in parentheses if, for example, it contains colons), which
gets applied to the {} expression's input (remember, all
filters have an input and an output).

    {foo: .bar}

will produce the JSON object `{"foo": 42}` if given the JSON
object `{"bar":42, "baz":43}` as its input. You can use this
to select particular fields of an object: if the input is an
object with "user", "title", "id", and "content" fields and
you just want "user" and "title", you can write

    {user: .user, title: .title}

Because that is so common, there's a shortcut syntax for it:
`{user, title}`.

If one of the expressions produces multiple results,
multiple dictionaries will be produced. If the input's

    {"user":"stedolan","titles":["JQ Primer", "More JQ"]}

then the expression

    {user, title: .titles[]}

will produce two outputs:

    {"user":"stedolan", "title": "JQ Primer"}
    {"user":"stedolan", "title": "More JQ"}

Putting parentheses around the key means it will be evaluated as an
expression. With the same input as above,

    {(.user): .titles}

produces

    {"stedolan": ["JQ Primer", "More JQ"]}

Variable references as keys use the value of the variable as
the key.  Without a value then the variable's name becomes the
key and its value becomes the value,

    "f o o" as $foo | "b a r" as $bar | {$foo, $bar:$foo}

produces

    {"foo":"f o o","b a r":"f o o"}

    Example: {user, title: .titles[]}
      Input: {"user":"stedolan","titles":["JQ Primer", "More JQ"]}
     Output: {"user":"stedolan", "title": "JQ Primer"}
             {"user":"stedolan", "title": "More JQ"}

    Example: {(.user): .titles}
      Input: {"user":"stedolan","titles":["JQ Primer", "More JQ"]}
     Output: {"stedolan": ["JQ Primer", "More JQ"]}


----------------------------------------------------------------------------
Recursive Descent: `..`
----------------------------------------------------------------------------

Recursively descends `.`, producing every value.  This is the
same as the zero-argument `recurse` builtin (see below).  This
is intended to resemble the XPath `//` operator.  Note that
`..a` does not work; use `.. | .a` instead.  In the example
below we use `.. | .a?` to find all the values of object keys
"a" in any object found "below" `.`.

This is particularly useful in conjunction with `path(EXP)`
(also see below) and the `?` operator.

    Example: .. | .a?
      Input: [[{"a":1}]]
     Output: 1



============================================================================
SECTION: Builtin operators and functions
============================================================================

Some jq operators (for instance, `+`) do different things
depending on the type of their arguments (arrays, numbers,
etc.). However, jq never does implicit type conversions. If you
try to add a string to an object you'll get an error message and
no result.

Please note that all numbers are converted to IEEE754 double precision
floating point representation. Arithmetic and logical operators are working
with these converted doubles. Results of all such operations are also limited
to the double precision.

The only exception to this behaviour of number is a snapshot of original number
literal. When a number which originally was provided as a literal is never
mutated until the end of the program then it is printed to the output in its
original literal form. This also includes cases when the original literal
would be truncated when converted to the IEEE754 double precision floating point
number.


----------------------------------------------------------------------------
Addition: `+`
----------------------------------------------------------------------------

The operator `+` takes two filters, applies them both
to the same input, and adds the results together. What
"adding" means depends on the types involved:

- **Numbers** are added by normal arithmetic.

- **Arrays** are added by being concatenated into a larger array.

- **Strings** are added by being joined into a larger string.

- **Objects** are added by merging, that is, inserting all
  the key-value pairs from both objects into a single
  combined object. If both objects contain a value for the
  same key, the object on the right of the `+` wins. (For
  recursive merge use the `*` operator.)

`null` can be added to any value, and returns the other
value unchanged.

    Example: .a + 1
      Input: {"a": 7}
     Output: 8

    Example: .a + .b
      Input: {"a": [1,2], "b": [3,4]}
     Output: [1,2,3,4]

    Example: .a + null
      Input: {"a": 1}
     Output: 1

    Example: .a + 1
      Input: {}
     Output: 1

    Example: {a: 1} + {b: 2} + {c: 3} + {a: 42}
      Input: null
     Output: {"a": 42, "b": 2, "c": 3}


----------------------------------------------------------------------------
Subtraction: `-`
----------------------------------------------------------------------------

As well as normal arithmetic subtraction on numbers, the `-`
operator can be used on arrays to remove all occurrences of
the second array's elements from the first array.

    Example: 4 - .a
      Input: {"a":3}
     Output: 1

    Example: . - ["xml", "yaml"]
      Input: ["xml", "yaml", "json"]
     Output: ["json"]


----------------------------------------------------------------------------
Multiplication, division, modulo: `*`, `/`, `%`
----------------------------------------------------------------------------

These infix operators behave as expected when given two numbers.
Division by zero raises an error. `x % y` computes x modulo y.

Multiplying a string by a number produces the concatenation of
that string that many times. `"x" * 0` produces `""`.

Dividing a string by another splits the first using the second
as separators.

Multiplying two objects will merge them recursively: this works
like addition but if both objects contain a value for the
same key, and the values are objects, the two are merged with
the same strategy.

    Example: 10 / . * 3
      Input: 5
     Output: 6

    Example: . / ", "
      Input: "a, b,c,d, e"
     Output: ["a","b,c,d","e"]

    Example: {"k": {"a": 1, "b": 2}} * {"k": {"a": 0,"c": 3}}
      Input: null
     Output: {"k": {"a": 0, "b": 2, "c": 3}}

    Example: .[] | (1 / .)?
      Input: [1,0,-1]
     Output: 1
             -1


----------------------------------------------------------------------------
`abs`
----------------------------------------------------------------------------

The builtin function `abs` is defined naively as: `if . < 0 then - . else . end`.

For numeric input, this is the absolute value.  See the
section on the identity filter for the implications of this
definition for numeric input.

To compute the absolute value of a number as a floating point number, you may wish use `fabs`.

    Example: map(abs)
      Input: [-10, -1.1, -1e-1]
     Output: [10,1.1,1e-1]


----------------------------------------------------------------------------
`length`
----------------------------------------------------------------------------

The builtin function `length` gets the length of various
different types of value:

- The length of a **string** is the number of Unicode
  codepoints it contains (which will be the same as its
  JSON-encoded length in bytes if it's pure ASCII).

- The length of a **number** is its absolute value.

- The length of an **array** is the number of elements.

- The length of an **object** is the number of key-value pairs.

- The length of **null** is zero.

- It is an error to use `length` on a **boolean**.

    Example: .[] | length
      Input: [[1,2], "string", {"a":2}, null, -5]
     Output: 2
             6
             1
             0
             5


----------------------------------------------------------------------------
`utf8bytelength`
----------------------------------------------------------------------------

The builtin function `utf8bytelength` outputs the number of
bytes used to encode a string in UTF-8.

    Example: utf8bytelength
      Input: "\u03bc"

</pblock>

     Output: 2


----------------------------------------------------------------------------
`keys`, `keys_unsorted`
----------------------------------------------------------------------------

The builtin function `keys`, when given an object, returns
its keys in an array.

The keys are sorted "alphabetically", by unicode codepoint
order. This is not an order that makes particular sense in
any particular language, but you can count on it being the
same for any two objects with the same set of keys,
regardless of locale settings.

When `keys` is given an array, it returns the valid indices
for that array: the integers from 0 to length-1.

The `keys_unsorted` function is just like `keys`, but if
the input is an object then the keys will not be sorted,
instead the keys will roughly be in insertion order.

    Example: keys
      Input: {"abc": 1, "abcd": 2, "Foo": 3}
     Output: ["Foo", "abc", "abcd"]

    Example: keys
      Input: [42,3,35]
     Output: [0,1,2]


----------------------------------------------------------------------------
`has(key)`
----------------------------------------------------------------------------

The builtin function `has` returns whether the input object
has the given key, or the input array has an element at the
given index.

`has($key)` has the same effect as checking whether `$key`
is a member of the array returned by `keys`, although `has`
will be faster.

    Example: map(has("foo"))
      Input: [{"foo": 42}, {}]
     Output: [true, false]

    Example: map(has(2))
      Input: [[0,1], ["a","b","c"]]
     Output: [false, true]


----------------------------------------------------------------------------
`in`
----------------------------------------------------------------------------

The builtin function `in` returns whether or not the input key is in the
given object, or the input index corresponds to an element
in the given array. It is, essentially, an inversed version
of `has`.

    Example: .[] | in({"foo": 42})
      Input: ["foo", "bar"]
     Output: true
             false

    Example: map(in([0,1]))
      Input: [2, 0]
     Output: [false, true]


----------------------------------------------------------------------------
`map(f)`, `map_values(f)`
----------------------------------------------------------------------------

For any filter `f`, `map(f)` and `map_values(f)` apply `f`
to each of the values in the input array or object, that is,
to the values of `.[]`.

In the absence of errors, `map(f)` always outputs an array
whereas `map_values(f)` outputs an array if given an array,
or an object if given an object.

When the input to `map_values(f)` is an object, the output
object has the same keys as the input object except for
those keys whose values when piped to `f` produce no values
at all.

The key difference between `map(f)` and `map_values(f)` is
that the former simply forms an array from all the values of
`($x|f)` for each value, `$x`, in the input array or object,
but `map_values(f)` only uses `first($x|f)`.

Specifically, for object inputs, `map_values(f)` constructs
the output object by examining in turn the value of
`first(.[$k]|f)` for each key, `$k`, of the input.  If this
expression produces no values, then the corresponding key
will be dropped; otherwise, the output object will have that
value at the key, `$k`.

Here are some examples to clarify the behavior of `map` and
`map_values` when applied to arrays. These examples assume the
input is `[1]` in all cases:

    map(.+1)          #=>  [2]
    map(., .)         #=>  [1,1]
    map(empty)        #=>  []

    map_values(.+1)   #=>  [2]
    map_values(., .)  #=>  [1]
    map_values(empty) #=>  []

`map(f)` is equivalent to `[.[] | f]` and
`map_values(f)` is equivalent to `.[] |= f`.

In fact, these are their implementations.

    Example: map(.+1)
      Input: [1,2,3]
     Output: [2,3,4]

    Example: map_values(.+1)
      Input: {"a": 1, "b": 2, "c": 3}
     Output: {"a": 2, "b": 3, "c": 4}

    Example: map(., .)
      Input: [1,2]
     Output: [1,1,2,2]

    Example: map_values(. // empty)
      Input: {"a": null, "b": true, "c": false}
     Output: {"b":true}


----------------------------------------------------------------------------
`pick(pathexps)`
----------------------------------------------------------------------------

Emit the projection of the input object or array defined by the
specified sequence of path expressions, such that if `p` is any
one of these specifications, then `(. | p)` will evaluate to the
same value as `(. | pick(pathexps) | p)`. For arrays, negative
indices and `.[m:n]` specifications should not be used.

    Example: pick(.a, .b.c, .x)
      Input: {"a": 1, "b": {"c": 2, "d": 3}, "e": 4}
     Output: {"a":1,"b":{"c":2},"x":null}

    Example: pick(.[2], .[0], .[0])
      Input: [1,2,3,4]
     Output: [1,null,3]


----------------------------------------------------------------------------
`path(path_expression)`
----------------------------------------------------------------------------

Outputs array representations of the given path expression
in `.`.  The outputs are arrays of strings (object keys)
and/or numbers (array indices).

Path expressions are jq expressions like `.a`, but also `.[]`.
There are two types of path expressions: ones that can match
exactly, and ones that cannot.  For example, `.a.b.c` is an
exact match path expression, while `.a[].b` is not.

`path(exact_path_expression)` will produce the array
representation of the path expression even if it does not
exist in `.`, if `.` is `null` or an array or an object.

`path(pattern)` will produce array representations of the
paths matching `pattern` if the paths exist in `.`.

Note that the path expressions are not different from normal
expressions.  The expression
`path(..|select(type=="boolean"))` outputs all the paths to
boolean values in `.`, and only those paths.

    Example: path(.a[0].b)
      Input: null
     Output: ["a",0,"b"]

    Example: [path(..)]
      Input: {"a":[{"b":1}]}
     Output: [[],["a"],["a",0],["a",0,"b"]]


----------------------------------------------------------------------------
`del(path_expression)`
----------------------------------------------------------------------------

The builtin function `del` removes a key and its corresponding
value from an object.

    Example: del(.foo)
      Input: {"foo": 42, "bar": 9001, "baz": 42}
     Output: {"bar": 9001, "baz": 42}

    Example: del(.[1, 2])
      Input: ["foo", "bar", "baz"]
     Output: ["foo"]


----------------------------------------------------------------------------
`getpath(PATHS)`
----------------------------------------------------------------------------

The builtin function `getpath` outputs the values in `.` found
at each path in `PATHS`.

    Example: getpath(["a","b"])
      Input: null
     Output: null

    Example: [getpath(["a","b"], ["a","c"])]
      Input: {"a":{"b":0, "c":1}}
     Output: [0, 1]


----------------------------------------------------------------------------
`setpath(PATHS; VALUE)`
----------------------------------------------------------------------------

The builtin function `setpath` sets the `PATHS` in `.` to `VALUE`.

    Example: setpath(["a","b"]; 1)
      Input: null
     Output: {"a": {"b": 1}}

    Example: setpath(["a","b"]; 1)
      Input: {"a":{"b":0}}
     Output: {"a": {"b": 1}}

    Example: setpath([0,"a"]; 1)
      Input: null
     Output: [{"a":1}]


----------------------------------------------------------------------------
`delpaths(PATHS)`
----------------------------------------------------------------------------

The builtin function `delpaths` deletes the `PATHS` in `.`.
`PATHS` must be an array of paths, where each path is an array
of strings and numbers.

    Example: delpaths([["a","b"]])
      Input: {"a":{"b":1},"x":{"y":2}}
     Output: {"a":{},"x":{"y":2}}


----------------------------------------------------------------------------
`to_entries`, `from_entries`, `with_entries(f)`
----------------------------------------------------------------------------

These functions convert between an object and an array of
key-value pairs. If `to_entries` is passed an object, then
for each `k: v` entry in the input, the output array
includes `{"key": k, "value": v}`.

`from_entries` does the opposite conversion, and `with_entries(f)`
is a shorthand for `to_entries | map(f) | from_entries`, useful for
doing some operation to all keys and values of an object.
`from_entries` accepts `"key"`, `"Key"`, `"name"`, `"Name"`,
`"value"`, and `"Value"` as keys.

    Example: to_entries
      Input: {"a": 1, "b": 2}
     Output: [{"key":"a", "value":1}, {"key":"b", "value":2}]

    Example: from_entries
      Input: [{"key":"a", "value":1}, {"key":"b", "value":2}]
     Output: {"a": 1, "b": 2}

    Example: with_entries(.key |= "KEY_" + .)
      Input: {"a": 1, "b": 2}
     Output: {"KEY_a": 1, "KEY_b": 2}


----------------------------------------------------------------------------
`select(boolean_expression)`
----------------------------------------------------------------------------

The function `select(f)` produces its input unchanged if
`f` returns true for that input, and produces no output
otherwise.

It's useful for filtering lists: `[1,2,3] | map(select(. >= 2))`
will give you `[2,3]`.

    Example: map(select(. >= 2))
      Input: [1,5,3,0,7]
     Output: [5,3,7]

    Example: .[] | select(.id == "second")
      Input: [{"id": "first", "val": 1}, {"id": "second", "val": 2}]
     Output: {"id": "second", "val": 2}


----------------------------------------------------------------------------
`arrays`, `objects`, `iterables`, `booleans`, `numbers`, `normals`, `finites`, `strings`, `nulls`, `values`, `scalars`
----------------------------------------------------------------------------

These built-ins select only inputs that are arrays, objects,
iterables (arrays or objects), booleans, numbers, normal
numbers, finite numbers, strings, null, non-null values, and
non-iterables, respectively.

    Example: .[]|numbers
      Input: [[],{},1,"foo",null,true,false]
     Output: 1


----------------------------------------------------------------------------
`empty`
----------------------------------------------------------------------------

`empty` returns no results. None at all. Not even `null`.

It's useful on occasion. You'll know if you need it :)

    Example: 1, empty, 2
      Input: null
     Output: 1
             2

    Example: [1,2,empty,3]
      Input: null
     Output: [1,2,3]


----------------------------------------------------------------------------
`error`, `error(message)`
----------------------------------------------------------------------------

Produces an error with the input value, or with the message
given as the argument. Errors can be caught with try/catch;
see below.

    Example: try error catch .
      Input: "error message"
     Output: "error message"

    Example: try error("invalid value: \(.)") catch .
      Input: 42
     Output: "invalid value: 42"


----------------------------------------------------------------------------
`halt`
----------------------------------------------------------------------------

Stops the jq program with no further outputs.  jq will exit
with exit status `0`.


----------------------------------------------------------------------------
`halt_error`, `halt_error(exit_code)`
----------------------------------------------------------------------------

Stops the jq program with no further outputs.  The input will
be printed on `stderr` as raw output (i.e., strings will not
have double quotes) with no decoration, not even a newline.

The given `exit_code` (defaulting to `5`) will be jq's exit
status.

For example, `"Error: something went wrong\n"|halt_error(1)`.


----------------------------------------------------------------------------
`$__loc__`
----------------------------------------------------------------------------

</pblock>

Produces an object with a "file" key and a "line" key, with
the filename and line number where `$__loc__` occurs, as
values.

    Example: try error("\($__loc__)") catch .
      Input: null
     Output: "{\"file\":\"<top-level>\",\"line\":1}"


----------------------------------------------------------------------------
`paths`, `paths(node_filter)`
----------------------------------------------------------------------------

`paths` outputs the paths to all the elements in its input
(except it does not output the empty list, representing .
itself).

`paths(f)` outputs the paths to any values for which `f` is `true`.
That is, `paths(type == "number")` outputs the paths to all numeric
values.

    Example: [paths]
      Input: [1,[[],{"a":2}]]
     Output: [[0],[1],[1,0],[1,1],[1,1,"a"]]

    Example: [paths(type == "number")]
      Input: [1,[[],{"a":2}]]
     Output: [[0],[1,1,"a"]]


----------------------------------------------------------------------------
`add`, `add(generator)`
----------------------------------------------------------------------------

The filter `add` takes as input an array, and produces as
output the elements of the array added together. This might
mean summed, concatenated or merged depending on the types
of the elements of the input array - the rules are the same
as those for the `+` operator (described above).

If the input is an empty array, `add` returns `null`.

`add(generator)` operates on the given generator rather than
the input.

    Example: add
      Input: ["a","b","c"]
     Output: "abc"

    Example: add
      Input: [1, 2, 3]
     Output: 6

    Example: add
      Input: []
     Output: null

    Example: add(.[].a)
      Input: [{"a":3}, {"a":5}, {"b":6}]
     Output: 8


----------------------------------------------------------------------------
`any`, `any(condition)`, `any(generator; condition)`
----------------------------------------------------------------------------

The filter `any` takes as input an array of boolean values,
and produces `true` as output if any of the elements of
the array are `true`.

If the input is an empty array, `any` returns `false`.

The `any(condition)` form applies the given condition to the
elements of the input array.

The `any(generator; condition)` form applies the given
condition to all the outputs of the given generator.

    Example: any
      Input: [true, false]
     Output: true

    Example: any
      Input: [false, false]
     Output: false

    Example: any
      Input: []
     Output: false


----------------------------------------------------------------------------
`all`, `all(condition)`, `all(generator; condition)`
----------------------------------------------------------------------------

The filter `all` takes as input an array of boolean values,
and produces `true` as output if all of the elements of
the array are `true`.

The `all(condition)` form applies the given condition to the
elements of the input array.

The `all(generator; condition)` form applies the given
condition to all the outputs of the given generator.

If the input is an empty array, `all` returns `true`.

    Example: all
      Input: [true, false]
     Output: false

    Example: all
      Input: [true, true]
     Output: true

    Example: all
      Input: []
     Output: true


----------------------------------------------------------------------------
`flatten`, `flatten(depth)`
----------------------------------------------------------------------------

The filter `flatten` takes as input an array of nested arrays,
and produces a flat array in which all arrays inside the original
array have been recursively replaced by their values. You can pass
an argument to it to specify how many levels of nesting to flatten.

`flatten(2)` is like `flatten`, but going only up to two
levels deep.

    Example: flatten
      Input: [1, [2], [[3]]]
     Output: [1, 2, 3]

    Example: flatten(1)
      Input: [1, [2], [[3]]]
     Output: [1, 2, [3]]

    Example: flatten
      Input: [[]]
     Output: []

    Example: flatten
      Input: [{"foo": "bar"}, [{"foo": "baz"}]]
     Output: [{"foo": "bar"}, {"foo": "baz"}]


----------------------------------------------------------------------------
`range(upto)`, `range(from; upto)`, `range(from; upto; by)`
----------------------------------------------------------------------------

The `range` function produces a range of numbers. `range(4; 10)`
produces 6 numbers, from 4 (inclusive) to 10 (exclusive). The numbers
are produced as separate outputs. Use `[range(4; 10)]` to get a range as
an array.

The one argument form generates numbers from 0 to the given
number, with an increment of 1.

The two argument form generates numbers from `from` to `upto`
with an increment of 1.

The three argument form generates numbers `from` to `upto`
with an increment of `by`.

    Example: range(2; 4)
      Input: null
     Output: 2
             3

    Example: [range(2; 4)]
      Input: null
     Output: [2,3]

    Example: [range(4)]
      Input: null
     Output: [0,1,2,3]

    Example: [range(0; 10; 3)]
      Input: null
     Output: [0,3,6,9]

    Example: [range(0; 10; -1)]
      Input: null
     Output: []

    Example: [range(0; -5; -1)]
      Input: null
     Output: [0,-1,-2,-3,-4]


----------------------------------------------------------------------------
`floor`
----------------------------------------------------------------------------

The `floor` function returns the floor of its numeric input.

    Example: floor
      Input: 3.14159
     Output: 3


----------------------------------------------------------------------------
`sqrt`
----------------------------------------------------------------------------

The `sqrt` function returns the square root of its numeric input.

    Example: sqrt
      Input: 9
     Output: 3


----------------------------------------------------------------------------
`tonumber`
----------------------------------------------------------------------------

The `tonumber` function parses its input as a number. It
will convert correctly-formatted strings to their numeric
equivalent, leave numbers alone, and give an error on all other input.

    Example: .[] | tonumber
      Input: [1, "1"]
     Output: 1
             1


----------------------------------------------------------------------------
`toboolean`
----------------------------------------------------------------------------

The `toboolean` function parses its input as a boolean. It
will convert correctly-formatted strings to their boolean
equivalent, leave booleans alone, and give an error on all other input.

    Example: .[] | toboolean
      Input: ["true", "false", true, false]
     Output: true
             false
             true
             false


----------------------------------------------------------------------------
`tostring`
----------------------------------------------------------------------------

The `tostring` function prints its input as a
string. Strings are left unchanged, and all other values are
JSON-encoded.

    Example: .[] | tostring
      Input: [1, "1", [1]]
     Output: "1"
             "1"
             "[1]"


----------------------------------------------------------------------------
`type`
----------------------------------------------------------------------------

The `type` function returns the type of its argument as a
string, which is one of null, boolean, number, string, array
or object.

    Example: map(type)
      Input: [0, false, [], {}, null, "hello"]
     Output: ["number", "boolean", "array", "object", "null", "string"]


----------------------------------------------------------------------------
`infinite`, `nan`, `isinfinite`, `isnan`, `isfinite`, `isnormal`
----------------------------------------------------------------------------

Some arithmetic operations can yield infinities and "not a
number" (NaN) values.  The `isinfinite` builtin returns `true`
if its input is infinite.  The `isnan` builtin returns `true`
if its input is a NaN.  The `infinite` builtin returns a
positive infinite value.  The `nan` builtin returns a NaN.
The `isnormal` builtin returns true if its input is a normal
number.

Note that division by zero raises an error.

Currently most arithmetic operations operating on infinities,
NaNs, and sub-normals do not raise errors.

    Example: .[] | (infinite * .) < 0
      Input: [-1, 1]
     Output: true
             false

    Example: infinite, nan | type
      Input: null
     Output: "number"
             "number"


----------------------------------------------------------------------------
`sort`, `sort_by(path_expression)`
----------------------------------------------------------------------------

The `sort` functions sorts its input, which must be an
array. Values are sorted in the following order:

* `null`
* `false`
* `true`
* numbers
* strings, in alphabetical order (by unicode codepoint value)
* arrays, in lexical order
* objects

The ordering for objects is a little complex: first they're
compared by comparing their sets of keys (as arrays in
sorted order), and if their keys are equal then the values
are compared key by key.

`sort_by` may be used to sort by a particular field of an
object, or by applying any jq filter. `sort_by(f)` compares
two elements by comparing the result of `f` on each element.
When `f` produces multiple values, it firstly compares the
first values, and the second values if the first values are
equal, and so on.

    Example: sort
      Input: [8,3,null,6]
     Output: [null,3,6,8]

    Example: sort_by(.foo)
      Input: [{"foo":4, "bar":10}, {"foo":3, "bar":10}, {"foo":2, "bar":1}]
     Output: [{"foo":2, "bar":1}, {"foo":3, "bar":10}, {"foo":4, "bar":10}]

    Example: sort_by(.foo, .bar)
      Input: [{"foo":4, "bar":10}, {"foo":3, "bar":20}, {"foo":2, "bar":1}, {"foo":3, "bar":10}]
     Output: [{"foo":2, "bar":1}, {"foo":3, "bar":10}, {"foo":3, "bar":20}, {"foo":4, "bar":10}]


----------------------------------------------------------------------------
`group_by(path_expression)`
----------------------------------------------------------------------------

`group_by(.foo)` takes as input an array, groups the
elements having the same `.foo` field into separate arrays,
and produces all of these arrays as elements of a larger
array, sorted by the value of the `.foo` field.

Any jq expression, not just a field access, may be used in
place of `.foo`. The sorting order is the same as described
in the `sort` function above.

    Example: group_by(.foo)
      Input: [{"foo":1, "bar":10}, {"foo":3, "bar":100}, {"foo":1, "bar":1}]
     Output: [[{"foo":1, "bar":10}, {"foo":1, "bar":1}], [{"foo":3, "bar":100}]]


----------------------------------------------------------------------------
`min`, `max`, `min_by(path_exp)`, `max_by(path_exp)`
----------------------------------------------------------------------------

Find the minimum or maximum element of the input array.

The `min_by(path_exp)` and `max_by(path_exp)` functions allow
you to specify a particular field or property to examine, e.g.
`min_by(.foo)` finds the object with the smallest `foo` field.

    Example: min
      Input: [5,4,2,7]
     Output: 2

    Example: max_by(.foo)
      Input: [{"foo":1, "bar":14}, {"foo":2, "bar":3}]
     Output: {"foo":2, "bar":3}


----------------------------------------------------------------------------
`unique`, `unique_by(path_exp)`
----------------------------------------------------------------------------

The `unique` function takes as input an array and produces
an array of the same elements, in sorted order, with
duplicates removed.

The `unique_by(path_exp)` function will keep only one element
for each value obtained by applying the argument. Think of it
as making an array by taking one element out of every group
produced by `group`.

    Example: unique
      Input: [1,2,5,3,5,3,1,3]
     Output: [1,2,3,5]

    Example: unique_by(.foo)

</pblock>

      Input: [{"foo": 1, "bar": 2}, {"foo": 1, "bar": 3}, {"foo": 4, "bar": 5}]
     Output: [{"foo": 1, "bar": 2}, {"foo": 4, "bar": 5}]

    Example: unique_by(length)
      Input: ["chunky", "bacon", "kitten", "cicada", "asparagus"]
     Output: ["bacon", "chunky", "asparagus"]


----------------------------------------------------------------------------
`reverse`
----------------------------------------------------------------------------

This function reverses an array.

    Example: reverse
      Input: [1,2,3,4]
     Output: [4,3,2,1]


----------------------------------------------------------------------------
`contains(element)`
----------------------------------------------------------------------------

The filter `contains(b)` will produce true if b is
completely contained within the input. A string B is
contained in a string A if B is a substring of A. An array B
is contained in an array A if all elements in B are
contained in any element in A. An object B is contained in
object A if all of the values in B are contained in the
value in A with the same key. All other types are assumed to
be contained in each other if they are equal.

    Example: contains("bar")
      Input: "foobar"
     Output: true

    Example: contains(["baz", "bar"])
      Input: ["foobar", "foobaz", "blarp"]
     Output: true

    Example: contains(["bazzzzz", "bar"])
      Input: ["foobar", "foobaz", "blarp"]
     Output: false

    Example: contains({foo: 12, bar: [{barp: 12}]})
      Input: {"foo": 12, "bar":[1,2,{"barp":12, "blip":13}]}
     Output: true

    Example: contains({foo: 12, bar: [{barp: 15}]})
      Input: {"foo": 12, "bar":[1,2,{"barp":12, "blip":13}]}
     Output: false


----------------------------------------------------------------------------
`indices(s)`
----------------------------------------------------------------------------

Outputs an array containing the indices in `.` where `s`
occurs.  The input may be an array, in which case if `s` is an
array then the indices output will be those where all elements
in `.` match those of `s`.

    Example: indices(", ")
      Input: "a,b, cd, efg, hijk"
     Output: [3,7,12]

    Example: indices(1)
      Input: [0,1,2,1,3,1,4]
     Output: [1,3,5]

    Example: indices([1,2])
      Input: [0,1,2,3,1,4,2,5,1,2,6,7]
     Output: [1,8]


----------------------------------------------------------------------------
`index(s)`, `rindex(s)`
----------------------------------------------------------------------------

Outputs the index of the first (`index`) or last (`rindex`)
occurrence of `s` in the input.

    Example: index(", ")
      Input: "a,b, cd, efg, hijk"
     Output: 3

    Example: index(1)
      Input: [0,1,2,1,3,1,4]
     Output: 1

    Example: index([1,2])
      Input: [0,1,2,3,1,4,2,5,1,2,6,7]
     Output: 1

    Example: rindex(", ")
      Input: "a,b, cd, efg, hijk"
     Output: 12

    Example: rindex(1)
      Input: [0,1,2,1,3,1,4]
     Output: 5

    Example: rindex([1,2])
      Input: [0,1,2,3,1,4,2,5,1,2,6,7]
     Output: 8


----------------------------------------------------------------------------
`inside`
----------------------------------------------------------------------------

The filter `inside(b)` will produce true if the input is
completely contained within b. It is, essentially, an
inversed version of `contains`.

    Example: inside("foobar")
      Input: "bar"
     Output: true

    Example: inside(["foobar", "foobaz", "blarp"])
      Input: ["baz", "bar"]
     Output: true

    Example: inside(["foobar", "foobaz", "blarp"])
      Input: ["bazzzzz", "bar"]
     Output: false

    Example: inside({"foo": 12, "bar":[1,2,{"barp":12, "blip":13}]})
      Input: {"foo": 12, "bar": [{"barp": 12}]}
     Output: true

    Example: inside({"foo": 12, "bar":[1,2,{"barp":12, "blip":13}]})
      Input: {"foo": 12, "bar": [{"barp": 15}]}
     Output: false


----------------------------------------------------------------------------
`startswith(str)`
----------------------------------------------------------------------------

Outputs `true` if . starts with the given string argument.

    Example: [.[]|startswith("foo")]
      Input: ["fo", "foo", "barfoo", "foobar", "barfoob"]
     Output: [false, true, false, true, false]


----------------------------------------------------------------------------
`endswith(str)`
----------------------------------------------------------------------------

Outputs `true` if . ends with the given string argument.

    Example: [.[]|endswith("foo")]
      Input: ["foobar", "barfoo"]
     Output: [false, true]


----------------------------------------------------------------------------
`combinations`, `combinations(n)`
----------------------------------------------------------------------------

Outputs all combinations of the elements of the arrays in the
input array. If given an argument `n`, it outputs all combinations
of `n` repetitions of the input array.

    Example: combinations
      Input: [[1,2], [3, 4]]
     Output: [1, 3]
             [1, 4]
             [2, 3]
             [2, 4]

    Example: combinations(2)
      Input: [0, 1]
     Output: [0, 0]
             [0, 1]
             [1, 0]
             [1, 1]


----------------------------------------------------------------------------
`ltrimstr(str)`
----------------------------------------------------------------------------

Outputs its input with the given prefix string removed, if it
starts with it.

    Example: [.[]|ltrimstr("foo")]
      Input: ["fo", "foo", "barfoo", "foobar", "afoo"]
     Output: ["fo","","barfoo","bar","afoo"]


----------------------------------------------------------------------------
`rtrimstr(str)`
----------------------------------------------------------------------------

Outputs its input with the given suffix string removed, if it
ends with it.

    Example: [.[]|rtrimstr("foo")]
      Input: ["fo", "foo", "barfoo", "foobar", "foob"]
     Output: ["fo","","bar","foobar","foob"]


----------------------------------------------------------------------------
`trimstr(str)`
----------------------------------------------------------------------------

Outputs its input with the given string removed at both ends, if it
starts or ends with it.

    Example: [.[]|trimstr("foo")]
      Input: ["fo", "foo", "barfoo", "foobarfoo", "foob"]
     Output: ["fo","","bar","bar","b"]


----------------------------------------------------------------------------
`trim`, `ltrim`, `rtrim`
----------------------------------------------------------------------------

`trim` trims both leading and trailing whitespace.

`ltrim` trims only leading (left side) whitespace.

`rtrim` trims only trailing (right side) whitespace.

Whitespace characters are the usual `" "`, `"\n"` `"\t"`, `"\r"`
and also all characters in the Unicode character database with the
whitespace property. Note that what considers whitespace might
change in the future.

    Example: trim, ltrim, rtrim
      Input: " abc "
     Output: "abc"
             "abc "
             " abc"


----------------------------------------------------------------------------
`explode`
----------------------------------------------------------------------------

Converts an input string into an array of the string's
codepoint numbers.

    Example: explode
      Input: "foobar"
     Output: [102,111,111,98,97,114]


----------------------------------------------------------------------------
`implode`
----------------------------------------------------------------------------

The inverse of explode.

    Example: implode
      Input: [65, 66, 67]
     Output: "ABC"


----------------------------------------------------------------------------
`split(str)`
----------------------------------------------------------------------------

Splits an input string on the separator argument.

`split` can also split on regex matches when called with
two arguments (see the regular expressions section below).

    Example: split(", ")
      Input: "a, b,c,d, e, "
     Output: ["a","b,c,d","e",""]


----------------------------------------------------------------------------
`join(str)`
----------------------------------------------------------------------------

Joins the array of elements given as input, using the
argument as separator. It is the inverse of `split`: that is,
running `split("foo") | join("foo")` over any input string
returns said input string.

Numbers and booleans in the input are converted to strings.
Null values are treated as empty strings. Arrays and objects
in the input are not supported.

    Example: join(", ")
      Input: ["a","b,c,d","e"]
     Output: "a, b,c,d, e"

    Example: join(" ")
      Input: ["a",1,2.3,true,null,false]
     Output: "a 1 2.3 true  false"


----------------------------------------------------------------------------
`ascii_downcase`, `ascii_upcase`
----------------------------------------------------------------------------

Emit a copy of the input string with its alphabetic characters (a-z and A-Z)
converted to the specified case.

    Example: ascii_upcase
      Input: "useful but not for é"
     Output: "USEFUL BUT NOT FOR é"


----------------------------------------------------------------------------
`while(cond; update)`
----------------------------------------------------------------------------

The `while(cond; update)` function allows you to repeatedly
apply an update to `.` until `cond` is false.

Note that `while(cond; update)` is internally defined as a
recursive jq function.  Recursive calls within `while` will
not consume additional memory if `update` produces at most one
output for each input.  See advanced topics below.

    Example: [while(.<100; .*2)]
      Input: 1
     Output: [1,2,4,8,16,32,64]


----------------------------------------------------------------------------
`repeat(exp)`
----------------------------------------------------------------------------

The `repeat(exp)` function allows you to repeatedly
apply expression `exp` to `.` until an error is raised.

Note that `repeat(exp)` is internally defined as a
recursive jq function.  Recursive calls within `repeat` will
not consume additional memory if `exp` produces at most one
output for each input.  See advanced topics below.

    Example: [repeat(.*2, error)?]
      Input: 1
     Output: [2]


----------------------------------------------------------------------------
`until(cond; next)`
----------------------------------------------------------------------------

The `until(cond; next)` function allows you to repeatedly
apply the expression `next`, initially to `.` then to its own
output, until `cond` is true.  For example, this can be used
to implement a factorial function (see below).

Note that `until(cond; next)` is internally defined as a
recursive jq function.  Recursive calls within `until()` will
not consume additional memory if `next` produces at most one
output for each input.  See advanced topics below.

    Example: [.,1]|until(.[0] < 1; [.[0] - 1, .[1] * .[0]])|.[1]
      Input: 4
     Output: 24


----------------------------------------------------------------------------
`recurse(f)`, `recurse`, `recurse(f; condition)`
----------------------------------------------------------------------------

The `recurse(f)` function allows you to search through a
recursive structure, and extract interesting data from all
levels. Suppose your input represents a filesystem:

    {"name": "/", "children": [
      {"name": "/bin", "children": [
        {"name": "/bin/ls", "children": []},
        {"name": "/bin/sh", "children": []}]},
      {"name": "/home", "children": [
        {"name": "/home/stephen", "children": [
          {"name": "/home/stephen/jq", "children": []}]}]}]}

Now suppose you want to extract all of the filenames
present. You need to retrieve `.name`, `.children[].name`,
`.children[].children[].name`, and so on. You can do this
with:

    recurse(.children[]) | .name

</pblock>

When called without an argument, `recurse` is equivalent to
`recurse(.[]?)`.

`recurse(f)` is identical to `recurse(f; true)` and can be
used without concerns about recursion depth.

`recurse(f; condition)` is a generator which begins by
emitting . and then emits in turn .|f, .|f|f, .|f|f|f, ...  so long
as the computed value satisfies the condition. For example,
to generate all the integers, at least in principle, one
could write `recurse(.+1; true)`.

The recursive calls in `recurse` will not consume additional
memory whenever `f` produces at most a single output for each
input.

    Example: recurse(.foo[])
      Input: {"foo":[{"foo": []}, {"foo":[{"foo":[]}]}]}
     Output: {"foo":[{"foo":[]},{"foo":[{"foo":[]}]}]}
             {"foo":[]}
             {"foo":[{"foo":[]}]}
             {"foo":[]}

    Example: recurse
      Input: {"a":0,"b":[1]}
     Output: {"a":0,"b":[1]}
             0
             [1]
             1

    Example: recurse(. * .; . < 20)
      Input: 2
     Output: 2
             4
             16


----------------------------------------------------------------------------
`walk(f)`
----------------------------------------------------------------------------

The `walk(f)` function applies f recursively to every
component of the input entity.  When an array is
encountered, f is first applied to its elements and then to
the array itself; when an object is encountered, f is first
applied to all the values and then to the object.  In
practice, f will usually test the type of its input, as
illustrated in the following examples.  The first example
highlights the usefulness of processing the elements of an
array of arrays before processing the array itself.  The second
example shows how all the keys of all the objects within the
input can be considered for alteration.

    Example: walk(if type == "array" then sort else . end)
      Input: [[4, 1, 7], [8, 5, 2], [3, 6, 9]]
     Output: [[1,4,7],[2,5,8],[3,6,9]]

    Example: walk( if type == "object" then with_entries( .key |= sub( "^_+"; "") ) else . end )
      Input: [ { "_a": { "__b": 2 } } ]
     Output: [{"a":{"b":2}}]


----------------------------------------------------------------------------
`have_literal_numbers`
----------------------------------------------------------------------------

This builtin returns true if jq's build configuration
includes support for preservation of input number literals.


----------------------------------------------------------------------------
`have_decnum`
----------------------------------------------------------------------------

This builtin returns true if jq was built with "decnum",
which is the current literal number preserving numeric
backend implementation for jq.


----------------------------------------------------------------------------
`$JQ_BUILD_CONFIGURATION`
----------------------------------------------------------------------------

This builtin binding shows the jq executable's build
configuration.  Its value has no particular format, but
it can be expected to be at least the `./configure`
command-line arguments, and may be enriched in the
future to include the version strings for the build
tooling used.

Note that this can be overridden in the command-line
with `--arg` and related options.


----------------------------------------------------------------------------
`$ENV`, `env`
----------------------------------------------------------------------------

`$ENV` is an object representing the environment variables as
set when the jq program started.

`env` outputs an object representing jq's current environment.

At the moment there is no builtin for setting environment
variables.

    Example: $ENV.PAGER
      Input: null
     Output: "less"

    Example: env.PAGER
      Input: null
     Output: "less"


----------------------------------------------------------------------------
`transpose`
----------------------------------------------------------------------------

Transpose a possibly jagged matrix (an array of arrays).
Rows are padded with nulls so the result is always rectangular.

    Example: transpose
      Input: [[1], [2,3]]
     Output: [[1,2],[null,3]]


----------------------------------------------------------------------------
`bsearch(x)`
----------------------------------------------------------------------------

`bsearch(x)` conducts a binary search for x in the input
array.  If the input is sorted and contains x, then
`bsearch(x)` will return its index in the array; otherwise, if
the array is sorted, it will return (-1 - ix) where ix is an
insertion point such that the array would still be sorted
after the insertion of x at ix.  If the array is not sorted,
`bsearch(x)` will return an integer that is probably of no
interest.

    Example: bsearch(0)
      Input: [0,1]
     Output: 0

    Example: bsearch(0)
      Input: [1,2,3]
     Output: -1

    Example: bsearch(4) as $ix | if $ix < 0 then .[-(1+$ix)] = 4 else . end
      Input: [1,2,3]
     Output: [1,2,3,4]


----------------------------------------------------------------------------
String interpolation: `\(exp)`
----------------------------------------------------------------------------

Inside a string, you can put an expression inside parens
after a backslash. Whatever the expression returns will be
interpolated into the string.

    Example: "The input was \(.), which is one less than \(.+1)"
      Input: 42
     Output: "The input was 42, which is one less than 43"


----------------------------------------------------------------------------
Convert to/from JSON
----------------------------------------------------------------------------

The `tojson` and `fromjson` builtins dump values as JSON texts
or parse JSON texts into values, respectively.  The `tojson`
builtin differs from `tostring` in that `tostring` returns strings
unmodified, while `tojson` encodes strings as JSON strings.

    Example: [.[]|tostring]
      Input: [1, "foo", ["foo"]]
     Output: ["1","foo","[\"foo\"]"]

    Example: [.[]|tojson]
      Input: [1, "foo", ["foo"]]
     Output: ["1","\"foo\"","[\"foo\"]"]

    Example: [.[]|tojson|fromjson]
      Input: [1, "foo", ["foo"]]
     Output: [1,"foo",["foo"]]


----------------------------------------------------------------------------
Format strings and escaping
----------------------------------------------------------------------------

The `@foo` syntax is used to format and escape strings,
which is useful for building URLs, documents in a language
like HTML or XML, and so forth. `@foo` can be used as a
filter on its own, the possible escapings are:

* `@text`:

  Calls `tostring`, see that function for details.

* `@json`:

  Serializes the input as JSON.

* `@html`:

  Applies HTML/XML escaping, by mapping the characters
  `<>&'"` to their entity equivalents `&lt;`, `&gt;`,
  `&amp;`, `&apos;`, `&quot;`.

* `@uri`:

  Applies percent-encoding, by mapping all reserved URI
  characters to a `%XX` sequence.

* `@urid`:

  The inverse of `@uri`, applies percent-decoding, by mapping
  all `%XX` sequences to their corresponding URI characters.

* `@csv`:

  The input must be an array, and it is rendered as CSV
  with double quotes for strings, and quotes escaped by
  repetition.

* `@tsv`:

  The input must be an array, and it is rendered as TSV
  (tab-separated values). Each input array will be printed as
  a single line. Fields are separated by a single
  tab (ascii `0x09`). Input characters line-feed (ascii `0x0a`),
  carriage-return (ascii `0x0d`), tab (ascii `0x09`) and
  backslash (ascii `0x5c`) will be output as escape sequences
  `\n`, `\r`, `\t`, `\\` respectively.

* `@sh`:

  The input is escaped suitable for use in a command-line
  for a POSIX shell. If the input is an array, the output
  will be a series of space-separated strings.

* `@base64`:

  The input is converted to base64 as specified by RFC 4648.

* `@base64d`:

  The inverse of `@base64`, input is decoded as specified by RFC 4648.
  Note\: If the decoded string is not UTF-8, the results are undefined.

This syntax can be combined with string interpolation in a
useful way. You can follow a `@foo` token with a string
literal. The contents of the string literal will *not* be
escaped. However, all interpolations made inside that string
literal will be escaped. For instance,

    @uri "https://www.google.com/search?q=\(.search)"

will produce the following output for the input
`{"search":"what is jq?"}`:

    "https://www.google.com/search?q=what%20is%20jq%3F"

Note that the slashes, question mark, etc. in the URL are
not escaped, as they were part of the string literal.

    Example: @html
      Input: "This works if x < y"
     Output: "This works if x &lt; y"

    Example: @sh "echo \(.)"
      Input: "O'Hara's Ale"
     Output: "echo 'O'\\''Hara'\\''s Ale'"

    Example: @base64
      Input: "This is a message"
     Output: "VGhpcyBpcyBhIG1lc3NhZ2U="

    Example: @base64d
      Input: "VGhpcyBpcyBhIG1lc3NhZ2U="
     Output: "This is a message"


----------------------------------------------------------------------------
Dates
----------------------------------------------------------------------------

jq provides some basic date handling functionality, with some
high-level and low-level builtins.  In all cases these
builtins deal exclusively with time in UTC.

The `fromdateiso8601` builtin parses datetimes in the ISO 8601
format to a number of seconds since the Unix epoch
(1970-01-01T00:00:00Z).  The `todateiso8601` builtin does the
inverse.

The `fromdate` builtin parses datetime strings.  Currently
`fromdate` only supports ISO 8601 datetime strings, but in the
future it will attempt to parse datetime strings in more
formats.

The `todate` builtin is an alias for `todateiso8601`.

The `now` builtin outputs the current time, in seconds since
the Unix epoch.

Low-level jq interfaces to the C-library time functions are
also provided: `strptime`, `strftime`, `strflocaltime`,
`mktime`, `gmtime`, and `localtime`.  Refer to your host
operating system's documentation for the format strings used
by `strptime` and `strftime`.  Note: these are not necessarily
stable interfaces in jq, particularly as to their localization
functionality.

The `gmtime` builtin consumes a number of seconds since the
Unix epoch and outputs a "broken down time" representation of
Greenwich Mean Time as an array of numbers representing
(in this order): the year, the month (zero-based), the day of
the month (one-based), the hour of the day, the minute of the
hour, the second of the minute, the day of the week, and the
day of the year -- all one-based unless otherwise stated.  The
day of the week number may be wrong on some systems for dates
before March 1st 1900, or after December 31 2099.

The `localtime` builtin works like the `gmtime` builtin, but
using the local timezone setting.

The `mktime` builtin consumes "broken down time"
representations of time output by `gmtime` and `strptime`.

The `strptime(fmt)` builtin parses input strings matching the
`fmt` argument.  The output is in the "broken down time"
representation consumed by `mktime` and output by `gmtime`.

The `strftime(fmt)` builtin formats a time (GMT) with the
given format.  The `strflocaltime` does the same, but using
the local timezone setting.

The format strings for `strptime` and `strftime` are described
in typical C library documentation.  The format string for ISO
8601 datetime is `"%Y-%m-%dT%H:%M:%SZ"`.

jq may not support some or all of this date functionality on
some systems. In particular, the `%u` and `%j` specifiers for
`strptime(fmt)` are not supported on macOS.

    Example: fromdate
      Input: "2015-03-05T23:51:47Z"
     Output: 1425599507

    Example: strptime("%Y-%m-%dT%H:%M:%SZ")
      Input: "2015-03-05T23:51:47Z"
     Output: [2015,2,5,23,51,47,4,63]

    Example: strptime("%Y-%m-%dT%H:%M:%SZ")|mktime
      Input: "2015-03-05T23:51:47Z"
     Output: 1425599507

</pblock>

----------------------------------------------------------------------------
SQL-Style Operators
----------------------------------------------------------------------------

jq provides a few SQL-style operators.

* `INDEX(stream; index_expression)`:

  This builtin produces an object whose keys are computed by
  the given index expression applied to each value from the
  given stream.

* `JOIN($idx; stream; idx_expr; join_expr)`:

  This builtin joins the values from the given stream to the
  given index.  The index's keys are computed by applying the
  given index expression to each value from the given stream.
  An array of the value in the stream and the corresponding
  value from the index is fed to the given join expression to
  produce each result.

* `JOIN($idx; stream; idx_expr)`:

  Same as `JOIN($idx; stream; idx_expr; .)`.

* `JOIN($idx; idx_expr)`:

  This builtin joins the input `.` to the given index, applying
  the given index expression to `.` to compute the index key.
  The join operation is as described above.

* `IN(s)`:

  This builtin outputs `true` if `.` appears in the given
  stream, otherwise it outputs `false`.

* `IN(source; s)`:

  This builtin outputs `true` if any value in the source stream
  appears in the second stream, otherwise it outputs `false`.


----------------------------------------------------------------------------
`builtins`
----------------------------------------------------------------------------

Returns a list of all builtin functions in the format `name/arity`.
Since functions with the same name but different arities are considered
separate functions, `all/0`, `all/1`, and `all/2` would all be present
in the list.



============================================================================
SECTION: Conditionals and Comparisons
============================================================================


----------------------------------------------------------------------------
`==`, `!=`
----------------------------------------------------------------------------

The expression 'a == b' will produce 'true' if the results of evaluating
a and b are equal (that is, if they represent equivalent JSON values) and
'false' otherwise. In particular, strings are never considered equal
to numbers.  In checking for the equality of JSON objects, the ordering of keys
is irrelevant.  If you're coming from JavaScript, please note that jq's `==` is like
JavaScript's `===`, the "strict equality" operator.

!= is "not equal", and 'a != b' returns the opposite value of 'a == b'

    Example: . == false
      Input: null
     Output: false

    Example: . == {"b": {"d": (4 + 1e-20), "c": 3}, "a":1}
      Input: {"a":1, "b": {"c": 3, "d": 4}}
     Output: true

    Example: .[] == 1
      Input: [1, 1.0, "1", "banana"]
     Output: true
             true
             false
             false


----------------------------------------------------------------------------
if-then-else-end
----------------------------------------------------------------------------

`if A then B else C end` will act the same as `B` if `A`
produces a value other than false or null, but act the same
as `C` otherwise.

`if A then B end` is the same as `if A then B else .  end`.
That is, the `else` branch is optional, and if absent is the
same as `.`. This also applies to `elif` with absent ending `else` branch.

Checking for false or null is a simpler notion of
"truthiness" than is found in JavaScript or Python, but it
means that you'll sometimes have to be more explicit about
the condition you want.  You can't test whether, e.g. a
string is empty using `if .name then A else B end`; you'll
need something like `if .name == "" then A else B end` instead.

If the condition `A` produces multiple results, then `B` is evaluated
once for each result that is not false or null, and `C` is evaluated
once for each false or null.

More cases can be added to an if using `elif A then B` syntax.

    Example: if . == 0 then
  "zero"
elif . == 1 then
  "one"
else
  "many"
end
      Input: 2
     Output: "many"


----------------------------------------------------------------------------
`>`, `>=`, `<=`, `<`
----------------------------------------------------------------------------

The comparison operators `>`, `>=`, `<=`, `<` return whether
their left argument is greater than, greater than or equal
to, less than or equal to or less than their right argument
(respectively).

The ordering is the same as that described for `sort`, above.

    Example: . < 5
      Input: 2
     Output: true


----------------------------------------------------------------------------
`and`, `or`, `not`
----------------------------------------------------------------------------

jq supports the normal Boolean operators `and`, `or`, `not`.
They have the same standard of truth as if expressions -
`false` and `null` are considered "false values", and
anything else is a "true value".

If an operand of one of these operators produces multiple
results, the operator itself will produce a result for each input.

`not` is in fact a builtin function rather than an operator,
so it is called as a filter to which things can be piped
rather than with special syntax, as in `.foo and .bar |
not`.

These three only produce the values `true` and `false`, and
so are only useful for genuine Boolean operations, rather
than the common Perl/Python/Ruby idiom of
"value_that_may_be_null or default". If you want to use this
form of "or", picking between two values rather than
evaluating a condition, see the `//` operator below.

    Example: 42 and "a string"
      Input: null
     Output: true

    Example: (true, false) or false
      Input: null
     Output: true
             false

    Example: (true, true) and (true, false)
      Input: null
     Output: true
             false
             true
             false

    Example: [true, false | not]
      Input: null
     Output: [false, true]


----------------------------------------------------------------------------
Alternative operator: `//`
----------------------------------------------------------------------------

The `//` operator produces all the values of its left-hand
side that are neither `false` nor `null`. If the
left-hand side produces no values other than `false` or
`null`, then `//` produces all the values of its right-hand
side.

A filter of the form `a // b` produces all the results of
`a` that are not `false` or `null`.  If `a` produces no
results, or no results other than `false` or `null`, then `a
// b` produces the results of `b`.

This is useful for providing defaults: `.foo // 1` will
evaluate to `1` if there's no `.foo` element in the
input. It's similar to how `or` is sometimes used in Python
(jq's `or` operator is reserved for strictly Boolean
operations).

Note: `some_generator // defaults_here` is not the same
as `some_generator | . // defaults_here`.  The latter will
produce default values for all non-`false`, non-`null`
values of the left-hand side, while the former will not.
Precedence rules can make this confusing.  For example, in
`false, 1 // 2` the left-hand side of `//` is `1`, not
`false, 1` -- `false, 1 // 2` parses the same way as `false,
(1 // 2)`.  In `(false, null, 1) | . // 42` the left-hand
side of `//` is `.`, which always produces just one value,
while in `(false, null, 1) // 42` the left-hand side is a
generator of three values, and since it produces a
value other `false` and `null`, the default `42` is not
produced.

    Example: empty // 42
      Input: null
     Output: 42

    Example: .foo // 42
      Input: {"foo": 19}
     Output: 19

    Example: .foo // 42
      Input: {}
     Output: 42

    Example: (false, null, 1) // 42
      Input: null
     Output: 1

    Example: (false, null, 1) | . // 42
      Input: null
     Output: 42
             42
             1


----------------------------------------------------------------------------
try-catch
----------------------------------------------------------------------------

Errors can be caught by using `try EXP catch EXP`.  The first
expression is executed, and if it fails then the second is
executed with the error message.  The output of the handler,
if any, is output as if it had been the output of the
expression to try.

The `try EXP` form uses `empty` as the exception handler.

    Example: try .a catch ". is not an object"
      Input: true
     Output: ". is not an object"

    Example: [.[]|try .a]
      Input: [{}, true, {"a":1}]
     Output: [null, 1]

    Example: try error("some exception") catch .
      Input: true
     Output: "some exception"


----------------------------------------------------------------------------
Breaking out of control structures
----------------------------------------------------------------------------

A convenient use of try/catch is to break out of control
structures like `reduce`, `foreach`, `while`, and so on.

For example:

    # Repeat an expression until it raises "break" as an
    # error, then stop repeating without re-raising the error.
    # But if the error caught is not "break" then re-raise it.
    try repeat(exp) catch if .=="break" then empty else error

jq has a syntax for named lexical labels to "break" or "go (back) to":

    label $out | ... break $out ...

The `break $label_name` expression will cause the program to
act as though the nearest (to the left) `label $label_name`
produced `empty`.

The relationship between the `break` and corresponding `label`
is lexical: the label has to be "visible" from the break.

To break out of a `reduce`, for example:

    label $out | reduce .[] as $item (null; if .==false then break $out else ... end)

The following jq program produces a syntax error:

    break $out

because no label `$out` is visible.


----------------------------------------------------------------------------
Error Suppression / Optional Operator: `?`
----------------------------------------------------------------------------

The `?` operator, used as `EXP?`, is shorthand for `try EXP`.

    Example: [.[] | .a?]
      Input: [{}, true, {"a":1}]
     Output: [null, 1]

    Example: [.[] | tonumber?]
      Input: ["1", "invalid", "3", 4]
     Output: [1, 3, 4]



============================================================================
SECTION: Regular expressions
============================================================================

jq uses the
[Oniguruma regular expression library](https://github.com/kkos/oniguruma/blob/master/doc/RE),
as do PHP, TextMate, Sublime Text, etc, so the
description here will focus on jq specifics.

Oniguruma supports several flavors of regular expression, so it is important to know
that jq uses the ["Perl NG" (Perl with named groups)](https://github.com/kkos/oniguruma/blob/master/doc/SYNTAX.md) flavor.

The jq regex filters are defined so that they can be used using
one of these patterns:

    STRING | FILTER(REGEX)
    STRING | FILTER(REGEX; FLAGS)
    STRING | FILTER([REGEX])
    STRING | FILTER([REGEX, FLAGS])

where:

* STRING, REGEX, and FLAGS are jq strings and subject to jq string interpolation;
* REGEX, after string interpolation, should be a valid regular expression;
* FILTER is one of `test`, `match`, or `capture`, as described below.

Since REGEX must evaluate to a JSON string, some characters that are needed
to form a regular expression must be escaped. For example, the regular expression
`\s` signifying a whitespace character would be written as `"\\s"`.

FLAGS is a string consisting of one of more of the supported flags:

* `g` - Global search (find all matches, not just the first)
* `i` - Case insensitive search
* `m` - Multi line mode (`.` will match newlines)
* `n` - Ignore empty matches
* `p` - Both s and m modes are enabled
* `s` - Single line mode (`^` -> `\A`, `$` -> `\Z`)
* `l` - Find longest possible matches
* `x` - Extended regex format (ignore whitespace and comments)

</pblock>

To match a whitespace with the `x` flag, use `\s`, e.g.

    jq -n '"a b" | test("a\\sb"; "x")'

Note that certain flags may also be specified within REGEX, e.g.

    jq -n '("test", "TEst", "teST", "TEST") | test("(?i)te(?-i)st")'

evaluates to: `true`, `true`, `false`, `false`.


----------------------------------------------------------------------------
`test(val)`, `test(regex; flags)`
----------------------------------------------------------------------------

Like `match`, but does not return match objects, only `true` or `false`
for whether or not the regex matches the input.

    Example: test("foo")
      Input: "foo"
     Output: true

    Example: .[] | test("a b c # spaces are ignored"; "ix")
      Input: ["xabcd", "ABC"]
     Output: true
             true


----------------------------------------------------------------------------
`match(val)`, `match(regex; flags)`
----------------------------------------------------------------------------

**match** outputs an object for each match it finds.  Matches have
the following fields:

* `offset` - offset in UTF-8 codepoints from the beginning of the input
* `length` - length in UTF-8 codepoints of the match
* `string` - the string that it matched
* `captures` - an array of objects representing capturing groups.

Capturing group objects have the following fields:

* `offset` - offset in UTF-8 codepoints from the beginning of the input
* `length` - length in UTF-8 codepoints of this capturing group
* `string` - the string that was captured
* `name` - the name of the capturing group (or `null` if it was unnamed)

Capturing groups that did not match anything return an offset of -1

    Example: match("(abc)+"; "g")
      Input: "abc abc"
     Output: {"offset": 0, "length": 3, "string": "abc", "captures": [{"offset": 0, "length": 3, "string": "abc", "name": null}]}
             {"offset": 4, "length": 3, "string": "abc", "captures": [{"offset": 4, "length": 3, "string": "abc", "name": null}]}

    Example: match("foo")
      Input: "foo bar foo"
     Output: {"offset": 0, "length": 3, "string": "foo", "captures": []}

    Example: match(["foo", "ig"])
      Input: "foo bar FOO"
     Output: {"offset": 0, "length": 3, "string": "foo", "captures": []}
             {"offset": 8, "length": 3, "string": "FOO", "captures": []}

    Example: match("foo (?<bar123>bar)? foo"; "ig")
      Input: "foo bar foo foo  foo"
     Output: {"offset": 0, "length": 11, "string": "foo bar foo", "captures": [{"offset": 4, "length": 3, "string": "bar", "name": "bar123"}]}
             {"offset": 12, "length": 8, "string": "foo  foo", "captures": [{"offset": -1, "length": 0, "string": null, "name": "bar123"}]}

    Example: [ match("."; "g")] | length
      Input: "abc"
     Output: 3


----------------------------------------------------------------------------
`capture(val)`, `capture(regex; flags)`
----------------------------------------------------------------------------

Collects the named captures in a JSON object, with the name
of each capture as the key, and the matched string as the
corresponding value.

    Example: capture("(?<a>[a-z]+)-(?<n>[0-9]+)")
      Input: "xyzzy-14"
     Output: { "a": "xyzzy", "n": "14" }


----------------------------------------------------------------------------
`scan(regex)`, `scan(regex; flags)`
----------------------------------------------------------------------------

Emit a stream of the non-overlapping substrings of the input
that match the regex in accordance with the flags, if any
have been specified.  If there is no match, the stream is empty.
To capture all the matches for each input string, use the idiom
`[ expr ]`, e.g. `[ scan(regex) ]`.  If the regex contains capturing
groups, the filter emits a stream of arrays, each of which contains
the captured strings.

    Example: scan("c")
      Input: "abcdefabc"
     Output: "c"
             "c"

    Example: scan("(a+)(b+)")
      Input: "abaabbaaabbb"
     Output: ["a","b"]
             ["aa","bb"]
             ["aaa","bbb"]


----------------------------------------------------------------------------
`split(regex; flags)`
----------------------------------------------------------------------------

Splits an input string on each regex match.

For backwards compatibility, when called with a single argument,
`split` splits on a string, not a regex.

    Example: split(", *"; null)
      Input: "ab,cd, ef"
     Output: ["ab","cd","ef"]


----------------------------------------------------------------------------
`splits(regex)`, `splits(regex; flags)`
----------------------------------------------------------------------------

These provide the same results as their `split` counterparts,
but as a stream instead of an array.

    Example: splits(", *")
      Input: "ab,cd,   ef, gh"
     Output: "ab"
             "cd"
             "ef"
             "gh"

    Example: splits(",? *"; "n")
      Input: "ab,cd ef,  gh"
     Output: "ab"
             "cd"
             "ef"
             "gh"


----------------------------------------------------------------------------
`sub(regex; tostring)`, `sub(regex; tostring; flags)`
----------------------------------------------------------------------------

Emit the string obtained by replacing the first match of
regex in the input string with `tostring`, after
interpolation.  `tostring` should be a jq string or a stream
of such strings, each of which may contain references to
named captures. The named captures are, in effect, presented
as a JSON object (as constructed by `capture`) to
`tostring`, so a reference to a captured variable named "x"
would take the form: `"\(.x)"`.

    Example: sub("[^a-z]*(?<x>[a-z]+)"; "Z\(.x)"; "g")
      Input: "123abc456def"
     Output: "ZabcZdef"

    Example: [sub("(?<a>.)"; "\(.a|ascii_upcase)", "\(.a|ascii_downcase)")]
      Input: "aB"
     Output: ["AB","aB"]


----------------------------------------------------------------------------
`gsub(regex; tostring)`, `gsub(regex; tostring; flags)`
----------------------------------------------------------------------------

`gsub` is like `sub` but all the non-overlapping occurrences of the regex are
replaced by `tostring`, after interpolation. If the second argument is a stream
of jq strings, then `gsub` will produce a corresponding stream of JSON strings.

    Example: gsub("(?<x>.)[^a]*"; "+\(.x)-")
      Input: "Abcabc"
     Output: "+A-+a-"

    Example: [gsub("p"; "a", "b")]
      Input: "p"
     Output: ["a","b"]



============================================================================
SECTION: Advanced features
============================================================================

Variables are an absolute necessity in most programming languages, but
they're relegated to an "advanced feature" in jq.

In most languages, variables are the only means of passing around
data. If you calculate a value, and you want to use it more than once,
you'll need to store it in a variable. To pass a value to another part
of the program, you'll need that part of the program to define a
variable (as a function parameter, object member, or whatever) in
which to place the data.

It is also possible to define functions in jq, although this is
is a feature whose biggest use is defining jq's standard library
(many jq functions such as `map` and `select` are in fact written
in jq).

jq has reduction operators, which are very powerful but a bit
tricky.  Again, these are mostly used internally, to define some
useful bits of jq's standard library.

It may not be obvious at first, but jq is all about generators
(yes, as often found in other languages).  Some utilities are
provided to help deal with generators.

Some minimal I/O support (besides reading JSON from standard
input, and writing JSON to standard output) is available.

Finally, there is a module/library system.


----------------------------------------------------------------------------
Variable / Symbolic Binding Operator: `... as $identifier | ...`
----------------------------------------------------------------------------

In jq, all filters have an input and an output, so manual
plumbing is not necessary to pass a value from one part of a program
to the next. Many expressions, for instance `a + b`, pass their input
to two distinct subexpressions (here `a` and `b` are both passed the
same input), so variables aren't usually necessary in order to use a
value twice.

For instance, calculating the average value of an array of numbers
requires a few variables in most languages - at least one to hold the
array, perhaps one for each element or for a loop counter. In jq, it's
simply `add / length` - the `add` expression is given the array and
produces its sum, and the `length` expression is given the array and
produces its length.

So, there's generally a cleaner way to solve most problems in jq than
defining variables. Still, sometimes they do make things easier, so jq
lets you define variables using `expression as $variable`. All
variable names start with `$`. Here's a slightly uglier version of the
array-averaging example:

    length as $array_length | add / $array_length

We'll need a more complicated problem to find a situation where using
variables actually makes our lives easier.


Suppose we have an array of blog posts, with "author" and "title"
fields, and another object which is used to map author usernames to
real names. Our input looks like:

    {"posts": [{"title": "First post", "author": "anon"},
               {"title": "A well-written article", "author": "person1"}],
     "realnames": {"anon": "Anonymous Coward",
                   "person1": "Person McPherson"}}

We want to produce the posts with the author field containing a real
name, as in:

    {"title": "First post", "author": "Anonymous Coward"}
    {"title": "A well-written article", "author": "Person McPherson"}

We use a variable, `$names`, to store the realnames object, so that we
can refer to it later when looking up author usernames:

    .realnames as $names | .posts[] | {title, author: $names[.author]}

The expression `exp as $x | ...` means: for each value of expression
`exp`, run the rest of the pipeline with the entire original input, and
with `$x` set to that value.  Thus `as` functions as something of a
foreach loop.

Just as `{foo}` is a handy way of writing `{foo: .foo}`, so
`{$foo}` is a handy way of writing `{foo: $foo}`.

Multiple variables may be declared using a single `as` expression by
providing a pattern that matches the structure of the input
(this is known as "destructuring"):

    . as {realnames: $names, posts: [$first, $second]} | ...

The variable declarations in array patterns (e.g., `. as
[$first, $second]`) bind to the elements of the array in from
the element at index zero on up, in order.  When there is no
value at the index for an array pattern element, `null` is
bound to that variable.

Variables are scoped over the rest of the expression that defines
them, so

    .realnames as $names | (.posts[] | {title, author: $names[.author]})

will work, but

    (.realnames as $names | .posts[]) | {title, author: $names[.author]}

won't.

For programming language theorists, it's more accurate to
say that jq variables are lexically-scoped bindings.  In
particular there's no way to change the value of a binding;
one can only setup a new binding with the same name, but which
will not be visible where the old one was.

    Example: .bar as $x | .foo | . + $x
      Input: {"foo":10, "bar":200}
     Output: 210

    Example: . as $i|[(.*2|. as $i| $i), $i]
      Input: 5
     Output: [10,5]

    Example: . as [$a, $b, {c: $c}] | $a + $b + $c
      Input: [2, 3, {"c": 4, "d": 5}]
     Output: 9

    Example: .[] as [$a, $b] | {a: $a, b: $b}
      Input: [[0], [0, 1], [2, 1, 0]]
     Output: {"a":0,"b":null}
             {"a":0,"b":1}
             {"a":2,"b":1}


----------------------------------------------------------------------------

</pblock>

Destructuring Alternative Operator: `?//`
----------------------------------------------------------------------------

The destructuring alternative operator provides a concise mechanism
for destructuring an input that can take one of several forms.

Suppose we have an API that returns a list of resources and events
associated with them, and we want to get the user_id and timestamp of
the first event for each resource. The API (having been clumsily
converted from XML) will only wrap the events in an array if the resource
has multiple events:

    {"resources": [{"id": 1, "kind": "widget", "events": {"action": "create", "user_id": 1, "ts": 13}},
                   {"id": 2, "kind": "widget", "events": [{"action": "create", "user_id": 1, "ts": 14}, {"action": "destroy", "user_id": 1, "ts": 15}]}]}

We can use the destructuring alternative operator to handle this structural change simply:

    .resources[] as {$id, $kind, events: {$user_id, $ts}} ?// {$id, $kind, events: [{$user_id, $ts}]} | {$user_id, $kind, $id, $ts}

Or, if we aren't sure if the input is an array of values or an object:

    .[] as [$id, $kind, $user_id, $ts] ?// {$id, $kind, $user_id, $ts} | ...

Each alternative need not define all of the same variables, but all named
variables will be available to the subsequent expression. Variables not
matched in the alternative that succeeded will be `null`:

    .resources[] as {$id, $kind, events: {$user_id, $ts}} ?// {$id, $kind, events: [{$first_user_id, $first_ts}]} | {$user_id, $first_user_id, $kind, $id, $ts, $first_ts}

Additionally, if the subsequent expression returns an error, the
alternative operator will attempt to try the next binding. Errors
that occur during the final alternative are passed through.

    [[3]] | .[] as [$a] ?// [$b] | if $a != null then error("err: \($a)") else {$a,$b} end

    Example: .[] as {$a, $b, c: {$d, $e}} ?// {$a, $b, c: [{$d, $e}]} | {$a, $b, $d, $e}
      Input: [{"a": 1, "b": 2, "c": {"d": 3, "e": 4}}, {"a": 1, "b": 2, "c": [{"d": 3, "e": 4}]}]
     Output: {"a":1,"b":2,"d":3,"e":4}
             {"a":1,"b":2,"d":3,"e":4}

    Example: .[] as {$a, $b, c: {$d}} ?// {$a, $b, c: [{$e}]} | {$a, $b, $d, $e}
      Input: [{"a": 1, "b": 2, "c": {"d": 3, "e": 4}}, {"a": 1, "b": 2, "c": [{"d": 3, "e": 4}]}]
     Output: {"a":1,"b":2,"d":3,"e":null}
             {"a":1,"b":2,"d":null,"e":4}

    Example: .[] as [$a] ?// [$b] | if $a != null then error("err: \($a)") else {$a,$b} end
      Input: [[3]]
     Output: {"a":null,"b":3}


----------------------------------------------------------------------------
Defining Functions
----------------------------------------------------------------------------

You can give a filter a name using "def" syntax:

    def increment: . + 1;

From then on, `increment` is usable as a filter just like a
builtin function (in fact, this is how many of the builtins
are defined). A function may take arguments:

    def map(f): [.[] | f];

Arguments are passed as _filters_ (functions with no
arguments), _not_ as values. The same argument may be
referenced multiple times with different inputs (here `f` is
run for each element of the input array).  Arguments to a
function work more like callbacks than like value arguments.
This is important to understand.  Consider:

    def foo(f): f|f;
    5|foo(.*2)

The result will be 20 because `f` is `.*2`, and during the
first invocation of `f` `.` will be 5, and the second time it
will be 10 (5 * 2), so the result will be 20.  Function
arguments are filters, and filters expect an input when
invoked.

If you want the value-argument behaviour for defining simple
functions, you can just use a variable:

    def addvalue(f): f as $f | map(. + $f);

Or use the short-hand:

    def addvalue($f): ...;

With either definition, `addvalue(.foo)` will add the current
input's `.foo` field to each element of the array.  Do note
that calling `addvalue(.[])` will cause the `map(. + $f)` part
to be evaluated once per value in the value of `.` at the call
site.

Multiple definitions using the same function name are allowed.
Each re-definition replaces the previous one for the same
number of function arguments, but only for references from
functions (or main program) subsequent to the re-definition.
See also the section below on scoping.

    Example: def addvalue(f): . + [f]; map(addvalue(.[0]))
      Input: [[1,2],[10,20]]
     Output: [[1,2,1], [10,20,10]]

    Example: def addvalue(f): f as $x | map(. + $x); addvalue(.[0])
      Input: [[1,2],[10,20]]
     Output: [[1,2,1,2], [10,20,1,2]]


----------------------------------------------------------------------------
Scoping
----------------------------------------------------------------------------

There are two types of symbols in jq: value bindings (a.k.a.,
"variables"), and functions.  Both are scoped lexically,
with expressions being able to refer only to symbols that
have been defined "to the left" of them.  The only exception
to this rule is that functions can refer to themselves so as
to be able to create recursive functions.

For example, in the following expression there is a binding
which is visible "to the right" of it, `... | .*3 as
$times_three | [. + $times_three] | ...`, but not "to the
left".  Consider this expression now, `... | (.*3 as
$times_three | [. + $times_three]) | ...`: here the binding
`$times_three` is _not_ visible past the closing parenthesis.


----------------------------------------------------------------------------
`isempty(exp)`
----------------------------------------------------------------------------

Returns true if `exp` produces no outputs, false otherwise.

    Example: isempty(empty)
      Input: null
     Output: true

    Example: isempty(.[])
      Input: []
     Output: true

    Example: isempty(.[])
      Input: [1,2,3]
     Output: false


----------------------------------------------------------------------------
`limit(n; expr)`
----------------------------------------------------------------------------

The `limit` function extracts up to `n` outputs from `expr`.

    Example: [limit(3; .[])]
      Input: [0,1,2,3,4,5,6,7,8,9]
     Output: [0,1,2]


----------------------------------------------------------------------------
`skip(n; expr)`
----------------------------------------------------------------------------

The `skip` function skips the first `n` outputs from `expr`.

    Example: [skip(3; .[])]
      Input: [0,1,2,3,4,5,6,7,8,9]
     Output: [3,4,5,6,7,8,9]


----------------------------------------------------------------------------
`first(expr)`, `last(expr)`, `nth(n; expr)`
----------------------------------------------------------------------------

The `first(expr)` and `last(expr)` functions extract the first
and last values from `expr`, respectively.

The `nth(n; expr)` function extracts the nth value output by `expr`.
Note that `nth(n; expr)` doesn't support negative values of `n`.

    Example: [first(range(.)), last(range(.)), nth(5; range(.))]
      Input: 10
     Output: [0,9,5]

    Example: [first(empty), last(empty), nth(5; empty)]
      Input: null
     Output: []


----------------------------------------------------------------------------
`first`, `last`, `nth(n)`
----------------------------------------------------------------------------

The `first` and `last` functions extract the first
and last values from any array at `.`.

The `nth(n)` function extracts the nth value of any array at `.`.

    Example: [range(.)]|[first, last, nth(5)]
      Input: 10
     Output: [0,9,5]


----------------------------------------------------------------------------
`reduce`
----------------------------------------------------------------------------

The `reduce` syntax allows you to combine all of the results of
an expression by accumulating them into a single answer.
The form is `reduce EXP as $var (INIT; UPDATE)`.
As an example, we'll pass `[1,2,3]` to this expression:

    reduce .[] as $item (0; . + $item)

For each result that `.[]` produces, `. + $item` is run to
accumulate a running total, starting from 0 as the input value.
In this example, `.[]` produces the results `1`, `2`, and `3`,
so the effect is similar to running something like this:

    0 | 1 as $item | . + $item |
        2 as $item | . + $item |
        3 as $item | . + $item

    Example: reduce .[] as $item (0; . + $item)
      Input: [1,2,3,4,5]
     Output: 15

    Example: reduce .[] as [$i,$j] (0; . + $i * $j)
      Input: [[1,2],[3,4],[5,6]]
     Output: 44

    Example: reduce .[] as {$x,$y} (null; .x += $x | .y += [$y])
      Input: [{"x":"a","y":1},{"x":"b","y":2},{"x":"c","y":3}]
     Output: {"x":"abc","y":[1,2,3]}


----------------------------------------------------------------------------
`foreach`
----------------------------------------------------------------------------

The `foreach` syntax is similar to `reduce`, but intended to
allow the construction of `limit` and reducers that produce
intermediate results.

The form is `foreach EXP as $var (INIT; UPDATE; EXTRACT)`.
As an example, we'll pass `[1,2,3]` to this expression:

    foreach .[] as $item (0; . + $item; [$item, . * 2])

Like the `reduce` syntax, `. + $item` is run for each result
that `.[]` produces, but `[$item, . * 2]` is run for each
intermediate values. In this example, since the intermediate
values are `1`, `3`, and `6`, the `foreach` expression produces
`[1,2]`, `[2,6]`, and `[3,12]`. So the effect is similar
to running something like this:

    0 | 1 as $item | . + $item | [$item, . * 2],
        2 as $item | . + $item | [$item, . * 2],
        3 as $item | . + $item | [$item, . * 2]

When `EXTRACT` is omitted, the identity filter is used.
That is, it outputs the intermediate values as they are.

    Example: foreach .[] as $item (0; . + $item)
      Input: [1,2,3,4,5]
     Output: 1
             3
             6
             10
             15

    Example: foreach .[] as $item (0; . + $item; [$item, . * 2])
      Input: [1,2,3,4,5]
     Output: [1,2]
             [2,6]
             [3,12]
             [4,20]
             [5,30]

    Example: foreach .[] as $item (0; . + 1; {index: ., $item})
      Input: ["foo", "bar", "baz"]
     Output: {"index":1,"item":"foo"}
             {"index":2,"item":"bar"}
             {"index":3,"item":"baz"}


----------------------------------------------------------------------------
Recursion
----------------------------------------------------------------------------

As described above, `recurse` uses recursion, and any jq
function can be recursive.  The `while` builtin is also
implemented in terms of recursion.

Tail calls are optimized whenever the expression to the left of
the recursive call outputs its last value.  In practice this
means that the expression to the left of the recursive call
should not produce more than one output for each input.

For example:

    def recurse(f): def r: ., (f | select(. != null) | r); r;

    def while(cond; update):
      def _while:
        if cond then ., (update | _while) else empty end;
      _while;

    def repeat(exp):
      def _repeat:
        exp, _repeat;
      _repeat;


----------------------------------------------------------------------------
Generators and iterators
----------------------------------------------------------------------------

Some jq operators and functions are actually generators in
that they can produce zero, one, or more values for each
input, just as one might expect in other programming
languages that have generators.  For example, `.[]`
generates all the values in its input (which must be an
array or an object), `range(0; 10)` generates the integers
between 0 and 10, and so on.

Even the comma operator is a generator, generating first
the values generated by the expression to the left of the
comma, then the values generated by the expression on the
right of the comma.

The `empty` builtin is the generator that produces zero

</pblock>

outputs.  The `empty` builtin backtracks to the preceding
generator expression.

All jq functions can be generators just by using builtin
generators.  It is also possible to construct new generators
using only recursion and the comma operator.  If
recursive calls are "in tail position" then the
generator will be efficient.  In the example below the
recursive call by `_range` to itself is in tail position.
The example shows off three advanced topics: tail recursion,
generator construction, and sub-functions.

    Example: def range(init; upto; by): def _range: if (by > 0 and . < upto) or (by < 0 and . > upto) then ., ((.+by)|_range) else empty end; if init == upto then empty elif by == 0 then init else init|_range end; range(0; 10; 3)
      Input: null
     Output: 0
             3
             6
             9

    Example: def while(cond; update): def _while: if cond then ., (update | _while) else empty end; _while; [while(.<100; .*2)]
      Input: 1
     Output: [1,2,4,8,16,32,64]



============================================================================
SECTION: Math
============================================================================

jq currently only has IEEE754 double-precision (64-bit) floating
point number support.

Besides simple arithmetic operators such as `+`, jq also has most
standard math functions from the C math library.  C math functions
that take a single input argument (e.g., `sin()`) are available as
zero-argument jq functions.  C math functions that take two input
arguments (e.g., `pow()`) are available as two-argument jq
functions that ignore `.`.  C math functions that take three input
arguments are available as three-argument jq functions that ignore
`.`.

Availability of standard math functions depends on the
availability of the corresponding math functions in your operating
system and C math library.  Unavailable math functions will be
defined but will raise an error.

One-input C math functions: `acos` `acosh` `asin` `asinh` `atan`
`atanh` `cbrt` `ceil` `cos` `cosh` `erf` `erfc` `exp` `exp10`
`exp2` `expm1` `fabs` `floor` `gamma` `j0` `j1` `lgamma` `log`
`log10` `log1p` `log2` `logb` `nearbyint` `rint` `round`
`significand` `sin` `sinh` `sqrt` `tan` `tanh` `tgamma` `trunc`
`y0` `y1`.

Two-input C math functions: `atan2` `copysign` `drem` `fdim`
`fmax` `fmin` `fmod` `frexp` `hypot` `jn` `ldexp` `modf`
`nextafter` `nexttoward` `pow` `remainder` `scalb` `scalbln` `yn`.

Three-input C math functions: `fma`.

See your system's manual for more information on each of these.



============================================================================
SECTION: I/O
============================================================================

At this time jq has minimal support for I/O, mostly in the
form of control over when inputs are read.  Two builtins functions
are provided for this, `input` and `inputs`, that read from the
same sources (e.g., `stdin`, files named on the command-line) as
jq itself.  These two builtins, and jq's own reading actions, can
be interleaved with each other.  They are commonly used in combination
with the null input option `-n` to prevent one input from being read
implicitly.

Two builtins provide minimal output capabilities, `debug`, and
`stderr`.  (Recall that a jq program's output values are always
output as JSON texts on `stdout`.) The `debug` builtin can have
application-specific behavior, such as for executables that use
the libjq C API but aren't the jq executable itself.  The `stderr`
builtin outputs its input in raw mode to stderr with no additional
decoration, not even a newline.

Most jq builtins are referentially transparent, and yield constant
and repeatable value streams when applied to constant inputs.
This is not true of I/O builtins.


----------------------------------------------------------------------------
`input`
----------------------------------------------------------------------------

Outputs one new input.

Note that when using `input` it is generally necessary to
invoke jq with the `-n` command-line option, otherwise
the first entity will be lost.

    echo 1 2 3 4 | jq '[., input]' # [1,2] [3,4]


----------------------------------------------------------------------------
`inputs`
----------------------------------------------------------------------------

Outputs all remaining inputs, one by one.

This is primarily useful for reductions over a program's
inputs.  Note that when using `inputs` it is generally necessary
to invoke jq with the `-n` command-line option, otherwise
the first entity will be lost.

    echo 1 2 3 | jq -n 'reduce inputs as $i (0; . + $i)' # 6


----------------------------------------------------------------------------
`debug`, `debug(msgs)`
----------------------------------------------------------------------------

These two filters are like `.` but have as a side-effect the
production of one or more messages on stderr.

The message produced by the `debug` filter has the form

    ["DEBUG:",<input-value>]

where `<input-value>` is a compact rendition of the input
value.  This format may change in the future.

The `debug(msgs)` filter is defined as `(msgs | debug | empty), .`
thus allowing great flexibility in the content of the message,
while also allowing multi-line debugging statements to be created.

For example, the expression:

    1 as $x | 2 | debug("Entering function foo with $x == \($x)", .) | (.+1)

would produce the value 3 but with the following two lines
being written to stderr:

    ["DEBUG:","Entering function foo with $x == 1"]
    ["DEBUG:",2]


----------------------------------------------------------------------------
`stderr`
----------------------------------------------------------------------------

Prints its input in raw and compact mode to stderr with no
additional decoration, not even a newline.


----------------------------------------------------------------------------
`input_filename`
----------------------------------------------------------------------------

Returns the name of the file whose input is currently being
filtered.  Note that this will not work well unless jq is
running in a UTF-8 locale.


----------------------------------------------------------------------------
`input_line_number`
----------------------------------------------------------------------------

Returns the line number of the input currently being filtered.



============================================================================
SECTION: Streaming
============================================================================

With the `--stream` option jq can parse input texts in a streaming
fashion, allowing jq programs to start processing large JSON texts
immediately rather than after the parse completes.  If you have a
single JSON text that is 1GB in size, streaming it will allow you
to process it much more quickly.

However, streaming isn't easy to deal with as the jq program will
have `[<path>, <leaf-value>]` (and a few other forms) as inputs.

Several builtins are provided to make handling streams easier.

The examples below use the streamed form of `["a",["b"]]`, which is
`[[0],"a"],[[1,0],"b"],[[1,0]],[[1]]`.

Streaming forms include `[<path>, <leaf-value>]` (to indicate any
scalar value, empty array, or empty object), and `[<path>]` (to
indicate the end of an array or object).  Future versions of jq
run with `--stream` and `--seq` may output additional forms such
as `["error message"]` when an input text fails to parse.


----------------------------------------------------------------------------
`truncate_stream(stream_expression)`
----------------------------------------------------------------------------

Consumes a number as input and truncates the corresponding
number of path elements from the left of the outputs of the
given streaming expression.

    Example: truncate_stream([[0],"a"],[[1,0],"b"],[[1,0]],[[1]])
      Input: 1
     Output: [[0],"b"]
             [[0]]


----------------------------------------------------------------------------
`fromstream(stream_expression)`
----------------------------------------------------------------------------

Outputs values corresponding to the stream expression's
outputs.

    Example: fromstream(1|truncate_stream([[0],"a"],[[1,0],"b"],[[1,0]],[[1]]))
      Input: null
     Output: ["b"]


----------------------------------------------------------------------------
`tostream`
----------------------------------------------------------------------------

The `tostream` builtin outputs the streamed form of its input.

    Example: . as $dot|fromstream($dot|tostream)|.==$dot
      Input: [0,[1,{"a":1},{"b":2}]]
     Output: true



============================================================================
SECTION: Assignment
============================================================================

Assignment works a little differently in jq than in most
programming languages. jq doesn't distinguish between references
to and copies of something - two objects or arrays are either
equal or not equal, without any further notion of being "the
same object" or "not the same object".

If an object has two fields which are arrays, `.foo` and `.bar`,
and you append something to `.foo`, then `.bar` will not get
bigger, even if you've previously set `.bar = .foo`.  If you're
used to programming in languages like Python, Java, Ruby,
JavaScript, etc. then you can think of it as though jq does a full
deep copy of every object before it does the assignment (for
performance it doesn't actually do that, but that's the general
idea).

This means that it's impossible to build circular values in jq
(such as an array whose first element is itself). This is quite
intentional, and ensures that anything a jq program can produce
can be represented in JSON.

All the assignment operators in jq have path expressions on the
left-hand side (LHS).  The right-hand side (RHS) provides values
to set to the paths named by the LHS path expressions.

Values in jq are always immutable.  Internally, assignment works
by using a reduction to compute new, replacement values for `.` that
have had all the desired assignments applied to `.`, then
outputting the modified value.  This might be made clear by this
example: `{a:{b:{c:1}}} | (.a.b|=3), .`.  This will output
`{"a":{"b":3}}` and `{"a":{"b":{"c":1}}}` because the last
sub-expression, `.`, sees the original value, not the modified
value.

Most users will want to use modification assignment operators,
such as `|=` or `+=`, rather than `=`.

Note that the LHS of assignment operators refers to a value in
`.`.  Thus `$var.foo = 1` won't work as expected (`$var.foo` is
not a valid or useful path expression in `.`); use `$var | .foo =
1` instead.

Note too that `.a,.b=0` does not set `.a` and `.b`, but
`(.a,.b)=0` sets both.


----------------------------------------------------------------------------
Update-assignment: `|=`
----------------------------------------------------------------------------

This is the "update" operator `|=`.  It takes a filter on the
right-hand side and works out the new value for the property
of `.` being assigned to by running the old value through this
expression. For instance, `(.foo, .bar) |= .+1` will build an
object with the `foo` field set to the input's `foo` plus 1,
and the `bar` field set to the input's `bar` plus 1.

The left-hand side can be any general path expression; see `path()`.

Note that the left-hand side of `|=` refers to a value in `.`.
Thus `$var.foo |= . + 1` won't work as expected (`$var.foo` is
not a valid or useful path expression in `.`); use `$var |
.foo |= . + 1` instead.

If the right-hand side outputs no values (i.e., `empty`), then
the left-hand side path will be deleted, as with `del(path)`.

If the right-hand side outputs multiple values, only the first
one will be used (COMPATIBILITY NOTE: in jq 1.5 and earlier
releases, it used to be that only the last one was used).

</pblock>

    Example: (..|select(type=="boolean")) |= if . then 1 else 0 end
      Input: [true,false,[5,true,[true,[false]],false]]
     Output: [1,0,[5,1,[1,[0]],0]]


----------------------------------------------------------------------------
Arithmetic update-assignment: `+=`, `-=`, `*=`, `/=`, `%=`, `//=`
----------------------------------------------------------------------------

jq has a few operators of the form `a op= b`, which are all
equivalent to `a |= . op b`. So, `+= 1` can be used to
increment values, being the same as `|= . + 1`.

    Example: .foo += 1
      Input: {"foo": 42}
     Output: {"foo": 43}


----------------------------------------------------------------------------
Plain assignment: `=`
----------------------------------------------------------------------------

This is the plain assignment operator.  Unlike the others, the
input to the right-hand side (RHS) is the same as the input to
the left-hand side (LHS) rather than the value at the LHS
path, and all values output by the RHS will be used (as shown
below).

If the RHS of `=` produces multiple values, then for each such
value jq will set the paths on the left-hand side to the value
and then it will output the modified `.`.  For example,
`(.a,.b) = range(2)` outputs `{"a":0,"b":0}`, then
`{"a":1,"b":1}`.  The "update" assignment forms (see above) do
not do this.

This example should show the difference between `=` and `|=`:

Provide input `{"a": {"b": 10}, "b": 20}` to the programs

    .a = .b

and

    .a |= .b

The former will set the `a` field of the input to the `b`
field of the input, and produce the output `{"a": 20, "b": 20}`.
The latter will set the `a` field of the input to the `a`
field's `b` field, producing `{"a": 10, "b": 20}`.

    Example: .a = .b
      Input: {"a": {"b": 10}, "b": 20}
     Output: {"a":20,"b":20}

    Example: .a |= .b
      Input: {"a": {"b": 10}, "b": 20}
     Output: {"a":10,"b":20}

    Example: (.a, .b) = range(3)
      Input: null
     Output: {"a":0,"b":0}
             {"a":1,"b":1}
             {"a":2,"b":2}

    Example: (.a, .b) |= range(3)
      Input: null
     Output: {"a":0,"b":0}


----------------------------------------------------------------------------
Complex assignments
----------------------------------------------------------------------------

Lots more things are allowed on the left-hand side of a jq assignment
than in most languages. We've already seen simple field accesses on
the left hand side, and it's no surprise that array accesses work just
as well:

    .posts[0].title = "JQ Manual"

What may come as a surprise is that the expression on the left may
produce multiple results, referring to different points in the input
document:

    .posts[].comments |= . + ["this is great"]

That example appends the string "this is great" to the "comments"
array of each post in the input (where the input is an object with a
field "posts" which is an array of posts).

When jq encounters an assignment like 'a = b', it records the "path"
taken to select a part of the input document while executing a. This
path is then used to find which part of the input to change while
executing the assignment. Any filter may be used on the
left-hand side of an equals - whichever paths it selects from the
input will be where the assignment is performed.

This is a very powerful operation. Suppose we wanted to add a comment
to blog posts, using the same "blog" input above. This time, we only
want to comment on the posts written by "stedolan". We can find those
posts using the "select" function described earlier:

    .posts[] | select(.author == "stedolan")

The paths provided by this operation point to each of the posts that
"stedolan" wrote, and we can comment on each of them in the same way
that we did before:

    (.posts[] | select(.author == "stedolan") | .comments) |=
        . + ["terrible."]



============================================================================
SECTION: Comments
============================================================================

You can write comments in your jq filters using `#`.

A `#` character (not part of a string) starts a comment.
All characters from `#` to the end of the line are ignored.

If the end of the line is preceded by an odd number of backslash
characters, the following line is also considered part of the
comment and is ignored.

For example, the following code outputs `[1,3,4,7]`

    [
      1,
      # foo \
      2,
      # bar \\
      3,
      4, # baz \\\
      5, \
      6,
      7
      # comment \
        comment \
        comment
    ]

Backslash continuing the comment on the next line can be useful
when writing the "shebang" for a jq script:

    #!/bin/sh --
    # total - Output the sum of the given arguments (or stdin)
    # usage: total [numbers...]
    # \
    exec jq --args -MRnf -- "$0" "$@"

    $ARGS.positional |
    reduce (
      if . == []
        then inputs
        else .[]
      end |
      . as $dot |
      try tonumber catch false |
      if not or isnan then
        @json "total: Invalid number \($dot).\n" | halt_error(1)
      end
    ) as $n (0; . + $n)

The `exec` line is considered a comment by jq, so it is ignored.
But it is not ignored by `sh`, since in `sh` a backslash at the
end of the line does not continue the comment.
With this trick, when the script is invoked as `total 1 2`,
`/bin/sh -- /path/to/total 1 2` will be run, and `sh` will then
run `exec jq --args -MRnf -- /path/to/total 1 2` replacing itself
with a `jq` interpreter invoked with the specified options (`-M`,
`-R`, `-n`, `--args`), that evaluates the current file (`$0`),
with the arguments (`$@`) that were passed to `sh`.



============================================================================
SECTION: Modules
============================================================================

jq has a library/module system.  Modules are files whose names end
in `.jq`.

Modules imported by a program are searched for in a default search
path (see below).  The `import` and `include` directives allow the
importer to alter this path.

Paths in the search path are subject to various substitutions.

For paths starting with `~/`, the user's home directory is
substituted for `~`.

For paths starting with `$ORIGIN/`, the directory where the jq
executable is located is substituted for `$ORIGIN`.

For paths starting with `./` or paths that are `.`, the path of
the including file is substituted for `.`.  For top-level programs
given on the command-line, the current directory is used.

Import directives can optionally specify a search path to which
the default is appended.

The default search path is the search path given to the `-L`
command-line option, else `["~/.jq", "$ORIGIN/../lib/jq",
"$ORIGIN/../lib"]`.

Null and empty string path elements terminate search path
processing.

A dependency with relative path `foo/bar` would be searched for in
`foo/bar.jq` and `foo/bar/bar.jq` in the given search path. This
is intended to allow modules to be placed in a directory along
with, for example, version control files, README files, and so on,
but also to allow for single-file modules.

Consecutive components with the same name are not allowed to avoid
ambiguities (e.g., `foo/foo`).

For example, with `-L$HOME/.jq` a module `foo` can be found in
`$HOME/.jq/foo.jq` and `$HOME/.jq/foo/foo.jq`.

If `.jq` exists in the user's home directory, and is a file (not a
directory), it is automatically sourced into the main program.


----------------------------------------------------------------------------
`import RelativePathString as NAME [<metadata>];`
----------------------------------------------------------------------------

Imports a module found at the given path relative to a
directory in a search path.  A `.jq` suffix will be added to
the relative path string.  The module's symbols are prefixed
with `NAME::`.

The optional metadata must be a constant jq expression.  It
should be an object with keys like `homepage` and so on.  At
this time jq only uses the `search` key/value of the metadata.
The metadata is also made available to users via the
`modulemeta` builtin.

The `search` key in the metadata, if present, should have a
string or array value (array of strings); this is the search
path to be prefixed to the top-level search path.


----------------------------------------------------------------------------
`include RelativePathString [<metadata>];`
----------------------------------------------------------------------------

Imports a module found at the given path relative to a
directory in a search path as if it were included in place.  A
`.jq` suffix will be added to the relative path string.  The
module's symbols are imported into the caller's namespace as
if the module's content had been included directly.

The optional metadata must be a constant jq expression.  It
should be an object with keys like `homepage` and so on.  At
this time jq only uses the `search` key/value of the metadata.
The metadata is also made available to users via the
`modulemeta` builtin.


----------------------------------------------------------------------------
`import RelativePathString as $NAME [<metadata>];`
----------------------------------------------------------------------------

Imports a JSON file found at the given path relative to a
directory in a search path.  A `.json` suffix will be added to
the relative path string.  The file's data will be available
as `$NAME::NAME`.

The optional metadata must be a constant jq expression.  It
should be an object with keys like `homepage` and so on.  At
this time jq only uses the `search` key/value of the metadata.
The metadata is also made available to users via the
`modulemeta` builtin.

The `search` key in the metadata, if present, should have a
string or array value (array of strings); this is the search
path to be prefixed to the top-level search path.


----------------------------------------------------------------------------
`module <metadata>;`
----------------------------------------------------------------------------

This directive is entirely optional.  It's not required for
proper operation.  It serves only the purpose of providing
metadata that can be read with the `modulemeta` builtin.

The metadata must be a constant jq expression.  It should be
an object with keys like `homepage`.  At this time jq doesn't
use this metadata, but it is made available to users via the
`modulemeta` builtin.


----------------------------------------------------------------------------
`modulemeta`
----------------------------------------------------------------------------

Takes a module name as input and outputs the module's metadata
as an object, with the module's imports (including metadata)
as an array value for the `deps` key and the module's defined
functions as an array value for the `defs` key.

Programs can use this to query a module's metadata, which they
could then use to, for example, search for, download, and
install missing dependencies.

</pblock>

# Tests are groups of three lines: program, input, expected output
# Blank lines and lines starting with # are ignored

#
# Simple value tests to check parser. Input is irrelevant
#

true
null
true

false
null
false

null
42
null

1
null
1


-1
null
-1

# FIXME: much more number testing needed

{}
null
{}

[]
null
[]

{x:-1},{x:-.},{x:-.|abs}
1
{"x":-1}
{"x":-1}
{"x":1}

# The input line starts with a 0xFEFF (byte order mark) codepoint
# No, there is no reason to have a byte order mark in UTF8 text.
# But apparently people do, so jq shouldn't break on it.
.
"byte order mark"
"byte order mark"

# We test escapes by matching them against Unicode codepoints
# FIXME: more tests needed for weird unicode stuff (e.g. utf16 pairs)
"Aa\r\n\t\b\f\u03bc"
null
"Aa\u000d\u000a\u0009\u0008\u000c\u03bc"

.
"Aa\r\n\t\b\f\u03bc"
"Aa\u000d\u000a\u0009\u0008\u000c\u03bc"

%%FAIL
"u\vw"
jq: error: Invalid escape at line 1, column 4 (while parsing '"\v"') at <top-level>, line 1, column 3:
    "u\vw"
      ^^

"inter\("pol" + "ation")"
null
"interpolation"

@text,@json,([1,.]|@csv,@tsv),@html,(@uri|.,@urid),@sh,(@base64|.,@base64d)
"!()<>&'\"\t"
"!()<>&'\"\t"
"\"!()<>&'\\\"\\t\""
"1,\"!()<>&'\"\"\t\""
"1\t!()<>&'\"\\t"
"!()&lt;&gt;&amp;&apos;&quot;\t"
"%21%28%29%3C%3E%26%27%22%09"
"!()<>&'\"\t"
"'!()<>&'\\''\"\t'"
"ISgpPD4mJyIJ"
"!()<>&'\"\t"

# regression test for #436
@base64
"foóbar\n"
"Zm/Ds2Jhcgo="

@base64d
"Zm/Ds2Jhcgo="
"foóbar\n"

@uri
"\u03bc"
"%CE%BC"

@urid
"%CE%BC"
"\u03bc"

@html "<b>\(.)</b>"
"<script>hax</script>"
"<b>&lt;script&gt;hax&lt;/script&gt;</b>"

[.[]|tojson|fromjson]
["foo", 1, ["a", 1, "b", 2, {"foo":"bar"}]]
["foo",1,["a",1,"b",2,{"foo":"bar"}]]

#
# Dictionary construction syntax
#

{a: 1}
null
{"a":1}

{a,b,(.d):.a,e:.b}
{"a":1, "b":2, "c":3, "d":"c"}
{"a":1, "b":2, "c":1, "e":2}

{"a",b,"a$\(1+1)"}
{"a":1, "b":2, "c":3, "a$2":4}
{"a":1, "b":2, "a$2":4}

%%FAIL
{(0):1}
jq: error: Cannot use number (0) as object key at <top-level>, line 1, column 3:
    {(0):1}
      ^

%%FAIL
{1+2:3}
jq: error: May need parentheses around object key expression at <top-level>, line 1, column 2:
    {1+2:3}
     ^^^

%%FAIL
{non_const:., (0):1}
jq: error: Cannot use number (0) as object key at <top-level>, line 1, column 16:
    {non_const:., (0):1}
                   ^

#
# Field access, piping
#

.foo
{"foo": 42, "bar": 43}
42

.foo | .bar
{"foo": {"bar": 42}, "bar": "badvalue"}
42

.foo.bar
{"foo": {"bar": 42}, "bar": "badvalue"}
42

.foo_bar
{"foo_bar": 2}
2

.["foo"].bar
{"foo": {"bar": 42}, "bar": "badvalue"}
42

."foo"."bar"
{"foo": {"bar": 20}}
20

.e0, .E1, .E-1, .E+1
{"e0": 1, "E1": 2, "E": 3}
1
2
2
4

[.[]|.foo?]
[1,[2],{"foo":3,"bar":4},{},{"foo":5}]
[3,null,5]

[.[]|.foo?.bar?]
[1,[2],[],{"foo":3},{"foo":{"bar":4}},{}]
[4,null]

[..]
[1,[[2]],{ "a":[1]}]
[[1,[[2]],{"a":[1]}],1,[[2]],[2],2,{"a":[1]},[1],1]

[.[]|.[]?]
[1,null,[],[1,[2,[[3]]]],[{}],[{"a":[1,[2]]}]]
[1,[2,[[3]]],{},{"a":[1,[2]]}]

[.[]|.[1:3]?]
[1,null,true,false,"abcdef",{},{"a":1,"b":2},[],[1,2,3,4,5],[1,2]]
[null,"bc",[],[2,3],[2]]

# chaining/suffix-list, with and without dot
map(try .a[] catch ., try .a.[] catch ., .a[]?, .a.[]?)
[{"a": [1,2]}, {"a": 123}]
[1,2,1,2,1,2,1,2,"Cannot iterate over number (123)","Cannot iterate over number (123)"]

# oss-fuzz #66070: objects[] leaks if a non-last element throws an error
try ["OK", (.[] | error)] catch ["KO", .]
{"a":["b"],"c":["d"]}
["KO",["b"]]

#
# Negative array indices
#

try (.foo[-1] = 0) catch .
null
"Out of bounds negative array index"

try (.foo[-2] = 0) catch .
null
"Out of bounds negative array index"

.[-1] = 5
[0,1,2]
[0,1,5]

.[-2] = 5
[0,1,2]
[0,5,2]

try (.[999999999] = 0) catch .
null
"Array index too large"

#
# Multiple outputs, iteration
#

.[]
[1,2,3]
1
2
3

1,1
[]
1
1

1,.
[]
1
[]

[.]
[2]
[[2]]

[[2]]
[3]
[[2]]

[{}]
[2]
[{}]

[.[]]
["a"]
["a"]

[(.,1),((.,.[]),(2,3))]
["a","b"]
[["a","b"],1,["a","b"],"a","b",2,3]

[([5,5][]),.,.[]]
[1,2,3]
[5,5,[1,2,3],1,2,3]

{x: (1,2)},{x:3} | .x
null
1
2
3

[.[-4,-3,-2,-1,0,1,2,3]]
[1,2,3]
[null,1,2,3,1,2,3,null]

[range(0;10)]
null
[0,1,2,3,4,5,6,7,8,9]

[range(0,1;3,4)]
null
[0,1,2, 0,1,2,3, 1,2, 1,2,3]

[range(0;10;3)]
null
[0,3,6,9]

[range(0;10;-1)]
null
[]

[range(0;-5;-1)]
null
[0,-1,-2,-3,-4]

[range(0,1;4,5;1,2)]
null
[0,1,2,3,0,2, 0,1,2,3,4,0,2,4, 1,2,3,1,3, 1,2,3,4,1,3]

[while(.<100; .*2)]
1
[1,2,4,8,16,32,64]

[(label $here | .[] | if .>1 then break $here else . end), "hi!"]
[0,1,2]
[0,1,"hi!"]

[(label $here | .[] | if .>1 then break $here else . end), "hi!"]
[0,2,1]
[0,"hi!"]

%%FAIL
. as $foo | break $foo
jq: error: $*label-foo is not defined at <top-level>, line 1, column 13:
    . as $foo | break $foo
                ^^^^^^^^^^

[.[]|[.,1]|until(.[0] < 1; [.[0] - 1, .[1] * .[0]])|.[1]]
[1,2,3,4,5]
[1,2,6,24,120]

[label $out | foreach .[] as $item ([3, null]; if .[0] < 1 then break $out else [.[0] -1, $item] end; .[1])]
[11,22,33,44,55,66,77,88,99]
[11,22,33]

[foreach range(5) as $item (0; $item)]
null
[0,1,2,3,4]

[foreach .[] as [$i, $j] (0; . + $i - $j)]
[[2,1], [5,3], [6,4]]
[1,3,5]

[foreach .[] as {a:$a} (0; . + $a; -.)]
[{"a":1}, {"b":2}, {"a":3, "b":4}]
[-1, -1, -4]

[-foreach -.[] as $x (0; . + $x)]
[1,2,3]
[1,3,6]

[foreach .[] / .[] as $i (0; . + $i)]
[1,2]
[1,3,3.5,4.5]

[foreach .[] as $x (0; . + $x) as $x | $x]
[1,2,3]
[1,3,6]

[limit(3; .[])]
[11,22,33,44,55,66,77,88,99]
[11,22,33]

[limit(0; error)]
"badness"
[]

[limit(1; 1, error)]
"badness"
[1]

try limit(-1; error) catch .
null
"limit doesn't support negative count"

[skip(3; .[])]
[1,2,3,4,5,6,7,8,9]
[4,5,6,7,8,9]

[skip(0,2,3,4; .[])]
[1,2,3]
[1,2,3,3]

[skip(3; .[])]
[]
[]

try skip(-1; error) catch .
null
"skip doesn't support negative count"

nth(1; 0,1,error("foo"))
null
1

[first(range(.)), last(range(.))]
10
[0,9]

[first(range(.)), last(range(.))]
0
[]

[nth(0,5,9,10,15; range(.)), try nth(-1; range(.)) catch .]
10
[0,5,9,"nth doesn't support negative indices"]

# Check that first(g) does not extract more than one value from g
first(1,error("foo"))
null
1

#
# Check that various builtins evaluate all arguments where appropriate,
# doing cartesian products where appropriate.
#

# Check that limit does work for each value produced by n!
[limit(5,7; range(9))]
null
[0,1,2,3,4,0,1,2,3,4,5,6]

# Same check for nth
[nth(5,7; range(9;0;-1))]
null
[4,2]

# Same check for range/3
[range(0,1,2;4,3,2;2,3)]
null
[0,2,0,3,0,2,0,0,0,1,3,1,1,1,1,1,2,2,2,2]

# Same check for range/1
[range(3,5)]
null
[0,1,2,0,1,2,3,4]

# Same check for index/1, rindex/1, indices/1
[(index(",","|"), rindex(",","|")), indices(",","|")]
"a,b|c,d,e||f,g,h,|,|,i,j"
[1,3,22,19,[1,5,7,12,14,16,18,20,22],[3,9,10,17,19]]

# Same check for join/1
join(",","/")
["a","b","c","d"]
"a,b,c,d"
"a/b/c/d"

[.[]|join("a")]
[[],[""],["",""],["","",""]]
["","","a","aa"]

# Same check for flatten/1
flatten(3,2,1)
[0, [1], [[2]], [[[3]]]]
[0,1,2,3]
[0,1,2,[3]]
[0,1,[2],[[3]]]


#
# Slices
#

[.[3:2], .[-5:4], .[:-2], .[-2:], .[3:3][1:], .[10:]]
[0,1,2,3,4,5,6]
[[], [2,3], [0,1,2,3,4], [5,6], [], []]

[.[3:2], .[-5:4], .[:-2], .[-2:], .[3:3][1:], .[10:]]
"abcdefghi"
["","","abcdefg","hi","",""]

del(.[2:4],.[0],.[-2:])
[0,1,2,3,4,5,6,7]
[1,4,5]

.[2:4] = ([], ["a","b"], ["a","b","c"])
[0,1,2,3,4,5,6,7]
[0,1,4,5,6,7]
[0,1,"a","b",4,5,6,7]
[0,1,"a","b","c",4,5,6,7]

# Slices at large offsets (issue #1108)
#
# This is written this way because [range(<large number>)] is
# significantly slower under valgrind than .[<large number>] = value.
#
# We range down rather than up so that we have just one realloc.
reduce range(65540;65536;-1) as $i ([]; .[$i] = $i)|.[65536:]
null
[null,65537,65538,65539,65540]

#
# Variables
#

1 as $x | 2 as $y | [$x,$y,$x]
null
[1,2,1]

[1,2,3][] as $x | [[4,5,6,7][$x]]
null
[5]
[6]
[7]

42 as $x | . | . | . + 432 | $x + 1
34324
43

1 + 2 as $x | -$x
null
-3

"x" as $x | "a"+"y" as $y | $x+","+$y
null
"x,ay"

1 as $x | [$x,$x,$x as $x | $x]
null
[1,1,1]

[1, {c:3, d:4}] as [$a, {c:$b, b:$c}] | $a, $b, $c
null
1
3
null

. as {as: $kw, "str": $str, ("e"+"x"+"p"): $exp} | [$kw, $str, $exp]
{"as": 1, "str": 2, "exp": 3}
[1, 2, 3]

.[] as [$a, $b] | [$b, $a]
[[1], [1, 2, 3]]
[null, 1]
[2, 1]

. as $i | . as [$i] | $i
[0]
0

. as [$i] | . as $i | $i
[0]
[0]

%%FAIL
. as [] | null
jq: error: syntax error, unexpected ']', expecting BINDING or '[' or '{' at <top-level>, line 1, column 7:
    . as [] | null
          ^

%%FAIL
. as {} | null
jq: error: syntax error, unexpected '}' at <top-level>, line 1, column 7:
    . as {} | null
          ^

%%FAIL
. as $foo | [$foo, $bar]
jq: error: $bar is not defined at <top-level>, line 1, column 20:
    . as $foo | [$foo, $bar]
                       ^^^^

%%FAIL
. as {(true):$foo} | $foo
jq: error: Cannot use boolean (true) as object key at <top-level>, line 1, column 8:
    . as {(true):$foo} | $foo
           ^^^^

# [.,(.[] | {x:.},.),.,.[]]

#
# Builtin functions
#

1+1
null
2

1+1
"wtasdf"
2.0

2-1
null
1

2-(-1)
null
3

1e+0+0.001e3
"I wonder what this will be?"
20e-1

.+4
15
19.0

.+null
{"a":42}
{"a":42}

null+.
null
null

.a+.b
{"a":42}
42

[1,2,3] + [.]
null
[1,2,3,null]

{"a":1} + {"b":2} + {"c":3}
"asdfasdf"
{"a":1, "b":2, "c":3}

"asdf" + "jkl;" + . + . + .
"some string"
"asdfjkl;some stringsome stringsome string"

"\u0000\u0020\u0000" + .
"\u0000\u0020\u0000"
"\u0000 \u0000\u0000 \u0000"

42 - .
11
31

[1,2,3,4,1] - [.,3]
1
[2,4]

[-1 as $x | 1,$x]
null
[1,-1]

[10 * 20, 20 / .]
4
[200, 5]

1 + 2 * 2 + 10 / 2
null
10

[16 / 4 / 2, 16 / 4 * 2, 16 - 4 - 2, 16 - 4 + 2]
null
[2, 8, 10, 14]

1e-19 + 1e-20 - 5e-21
null
1.05e-19

1 / 1e-17
null
1e+17

9E999999999, 9999999999E999999990, 1E-999999999, 0.000000001E-999999990
null
9E+999999999
9.999999999E+999999999
1E-999999999
1E-999999999

5E500000000 > 5E-5000000000, 10000E500000000 > 10000E-5000000000
null
true
true

# #2825
(1e999999999, 10e999999999) > (1e-1147483646, 0.1e-1147483646)
null
true
true
true
true

25 % 7
null
4

49732 % 472
null
172

[(infinite, -infinite) % (1, -1, infinite)]
null
[0,0,0,0,0,-1]

[nan % 1, 1 % nan | isnan]
null
[true,true]

1 + tonumber + ("10" | tonumber)
4
15

"123\u0000456" | try tonumber catch .
null
"string (\"123\\u0000456\") cannot be parsed as a number"

map(toboolean)
["false","true",false,true]
[false,true,false,true]

.[] | try toboolean catch .
[null,0,"tru","truee","fals","falsee",[],{}]
"null (null) cannot be parsed as a boolean"
"number (0) cannot be parsed as a boolean"
"string (\"tru\") cannot be parsed as a boolean"
"string (\"truee\") cannot be parsed as a boolean"
"string (\"fals\") cannot be parsed as a boolean"
"string (\"falsee\") cannot be parsed as a boolean"
"array ([]) cannot be parsed as a boolean"
"object ({}) cannot be parsed as a boolean"

"true\u0000x", "false\u0000" | try toboolean catch .
null
"string (\"true\\u0000x\") cannot be parsed as a boolean"
"string (\"false\\u0000\") cannot be parsed as a boolean"

[{"a":42},.object,10,.num,false,true,null,"b",[1,4]] | .[] as $x | [$x == .[]]
{"object": {"a":42}, "num":10.0}
[true,  true,  false, false, false, false, false, false, false]
[true,  true,  false, false, false, false, false, false, false]
[false, false, true,  true,  false, false, false, false, false]
[false, false, true,  true,  false, false, false, false, false]
[false, false, false, false, true,  false, false, false, false]
[false, false, false, false, false, true,  false, false, false]
[false, false, false, false, false, false, true,  false, false]
[false, false, false, false, false, false, false, true,  false]
[false, false, false, false, false, false, false, false, true ]

[.[] | length]
[[], {}, [1,2], {"a":42}, "asdf", "\u03bc"]
[0, 0, 2, 1, 4, 1]

utf8bytelength
"asdf\u03bc"
6

[.[] | try utf8bytelength catch .]
[[], {}, [1,2], 55, true, false]

</pblock>

["array ([]) only strings have UTF-8 byte length","object ({}) only strings have UTF-8 byte length","array ([1,2]) only strings have UTF-8 byte length","number (55) only strings have UTF-8 byte length","boolean (true) only strings have UTF-8 byte length","boolean (false) only strings have UTF-8 byte length"]


map(keys)
[{}, {"abcd":1,"abc":2,"abcde":3}, {"x":1, "z": 3, "y":2}]
[[], ["abc","abcd","abcde"], ["x","y","z"]]

[1,2,empty,3,empty,4]
null
[1,2,3,4]

map(add)
[[], [1,2,3], ["a","b","c"], [[3],[4,5],[6]], [{"a":1}, {"b":2}, {"a":3}]]
[null, 6, "abc", [3,4,5,6], {"a":3, "b": 2}]

map_values(.+1)
[0,1,2]
[1,2,3]

[add(null), add(range(range(10))), add(empty), add(10,range(10))]
null
[null,120,null,55]

# Real-world use case for add(empty)
.sum = add(.arr[])
{"arr":[]}
{"arr":[],"sum":null}

add({(.[]):1}) | keys
["a","a","b","a","d","b","d","a","d"]
["a","b","d"]

#
# User-defined functions
# Oh god.
#

def f: . + 1; def g: def g: . + 100; f | g | f; (f | g), g
3.0
106.0
105.0

def f: (1000,2000); f
123412345
1000
2000

def f(a;b;c;d;e;f): [a+1,b,c,d,e,f]; f(.[0];.[1];.[0];.[0];.[0];.[0])
[1,2]
[2,2,1,1,1,1]

def f: 1; def g: f, def f: 2; def g: 3; f, def f: g; f, g; def f: 4; [f, def f: g; def g: 5; f, g]+[f,g]
null
[4,1,2,3,3,5,4,1,2,3,3]

# Test precedence of 'def' vs '|'
def a: 0; . | a
null
0

# Many arguments
def f(a;b;c;d;e;f;g;h;i;j): [j,i,h,g,f,e,d,c,b,a]; f(.[0];.[1];.[2];.[3];.[4];.[5];.[6];.[7];.[8];.[9])
[0,1,2,3,4,5,6,7,8,9]
[9,8,7,6,5,4,3,2,1,0]

([1,2] + [4,5])
[1,2,3]
[1,2,4,5]

true
[1]
true

null,1,null
"hello"
null
1
null

[1,2,3]
[5,6]
[1,2,3]

[.[]|floor]
[-1.1,1.1,1.9]
[-2, 1, 1]

[.[]|sqrt]
[4,9]
[2,3]

(add / length) as $m | map((. - $m) as $d | $d * $d) | add / length | sqrt
[2,4,4,4,5,5,7,9]
2

# Should write a test that calls the -lm function from C (or bc(1)) to
# check that they match the corresponding jq functions.  However,
# there's so little template code standing between that it suffices to
# test a handful of these.  The results were checked by eye against
# bc(1).
atan * 4 * 1000000|floor / 1000000
1
3.141592

[(3.141592 / 2) * (range(0;20) / 20)|cos * 1000000|floor / 1000000]
null
[1,0.996917,0.987688,0.972369,0.951056,0.923879,0.891006,0.85264,0.809017,0.760406,0.707106,0.649448,0.587785,0.522498,0.45399,0.382683,0.309017,0.233445,0.156434,0.078459]

[(3.141592 / 2) * (range(0;20) / 20)|sin * 1000000|floor / 1000000]
null
[0,0.078459,0.156434,0.233445,0.309016,0.382683,0.45399,0.522498,0.587785,0.649447,0.707106,0.760405,0.809016,0.85264,0.891006,0.923879,0.951056,0.972369,0.987688,0.996917]


def f(x): x | x; f([.], . + [42])
[1,2,3]
[[[1,2,3]]]
[[1,2,3],42]
[[1,2,3,42]]
[1,2,3,42,42]

# test multiple function arities and redefinition
def f: .+1; def g: f; def f: .+100; def f(a):a+.+11; [(g|f(20)), f]
1
[33,101]

# test closures and lexical scoping
def id(x):x; 2000 as $x | def f(x):1 as $x | id([$x, x, x]); def g(x): 100 as $x | f($x,$x+x); g($x)
"more testing"
[1,100,2100.0,100,2100.0]

# test def f($a) syntax
def x(a;b): a as $a | b as $b | $a + $b; def y($a;$b): $a + $b; def check(a;b): [x(a;b)] == [y(a;b)]; check(.[];.[]*2)
[1,2,3]
true

# test backtracking through function calls and returns
# this test is *evil*
[[20,10][1,0] as $x | def f: (100,200) as $y | def g: [$x + $y, .]; . + $x | g; f[0] | [f][0][1] | f]
999999999
[[110.0, 130.0], [210.0, 130.0], [110.0, 230.0], [210.0, 230.0], [120.0, 160.0], [220.0, 160.0], [120.0, 260.0], [220.0, 260.0]]

# test recursion
def fac: if . == 1 then 1 else . * (. - 1 | fac) end; [.[] | fac]
[1,2,3,4]
[1,2,6,24]

# test stack overflow and reallocation
# this test is disabled for now, it takes a realllllly long time.
# def f: if length > 1000 then . else .+[1]|f end; f | length
# []
# 1001

reduce .[] as $x (0; . + $x)
[1,2,4]
7

reduce .[] as [$i, {j:$j}] (0; . + $i - $j)
[[2,{"j":1}], [5,{"j":3}], [6,{"j":4}]]
5

reduce [[1,2,10], [3,4,10]][] as [$i,$j] (0; . + $i * $j)
null
14

[-reduce -.[] as $x (0; . + $x)]
[1,2,3]
[6]

[reduce .[] / .[] as $i (0; . + $i)]
[1,2]
[4.5]

reduce .[] as $x (0; . + $x) as $x | $x
[1,2,3]
6

# This, while useless, should still compile.
reduce . as $n (.; .)
null
null

# Destructuring
. as {$a, b: [$c, {$d}]} | [$a, $c, $d]
{"a":1, "b":[2,{"d":3}]}
[1,2,3]

. as {$a, $b:[$c, $d]}| [$a, $b, $c, $d]
{"a":1, "b":[2,{"d":3}]}
[1,[2,{"d":3}],2,{"d":3}]

# Destructuring with alternation
.[] | . as {$a, b: [$c, {$d}]} ?// [$a, {$b}, $e] ?// $f | [$a, $b, $c, $d, $e, $f]
[{"a":1, "b":[2,{"d":3}]}, [4, {"b":5, "c":6}, 7, 8, 9], "foo"]
[1, null, 2, 3, null, null]
[4, 5, null, null, 7, null]
[null, null, null, null, null, "foo"]

# Destructuring DUP/POP issues
.[] | . as {a:$a} ?// {a:$a} ?// {a:$a} | $a
[[3],[4],[5],6]
# Runtime error: "jq: Cannot index array with string (\"c\")"

.[] as {a:$a} ?// {a:$a} ?// {a:$a} | $a
[[3],[4],[5],6]
# Runtime error: "jq: Cannot index array with string (\"c\")"

[[3],[4],[5],6][] | . as {a:$a} ?// {a:$a} ?// {a:$a} | $a
null
# Runtime error: "jq: Cannot index array with string (\"c\")"

[[3],[4],[5],6] | .[] as {a:$a} ?// {a:$a} ?// {a:$a} | $a
null
# Runtime error: "jq: Cannot index array with string (\"c\")"

.[] | . as {a:$a} ?// {a:$a} ?// $a | $a
[[3],[4],[5],6]
[3]
[4]
[5]
6

.[] as {a:$a} ?// {a:$a} ?// $a | $a
[[3],[4],[5],6]
[3]
[4]
[5]
6

[[3],[4],[5],6][] | . as {a:$a} ?// {a:$a} ?// $a | $a
null
[3]
[4]
[5]
6

[[3],[4],[5],6] | .[] as {a:$a} ?// {a:$a} ?// $a | $a
null
[3]
[4]
[5]
6

.[] | . as {a:$a} ?// $a ?// {a:$a} | $a
[[3],[4],[5],6]
[3]
[4]
[5]
6

.[] as {a:$a} ?// $a ?// {a:$a} | $a
[[3],[4],[5],6]
[3]
[4]
[5]
6

[[3],[4],[5],6][] | . as {a:$a} ?// $a ?// {a:$a} | $a
null
[3]
[4]
[5]
6

[[3],[4],[5],6] | .[] as {a:$a} ?// $a ?// {a:$a} | $a
null
[3]
[4]
[5]
6

.[] | . as $a ?// {a:$a} ?// {a:$a} | $a
[[3],[4],[5],6]
[3]
[4]
[5]
6

.[] as $a ?// {a:$a} ?// {a:$a} | $a
[[3],[4],[5],6]
[3]
[4]
[5]
6

[[3],[4],[5],6][] | . as $a ?// {a:$a} ?// {a:$a} | $a
null
[3]
[4]
[5]
6

[[3],[4],[5],6] | .[] as $a ?// {a:$a} ?// {a:$a} | $a
null
[3]
[4]
[5]
6

. as $dot|any($dot[];not)
[1,2,3,4,true,false,1,2,3,4,5]
true

. as $dot|any($dot[];not)
[1,2,3,4,true]
false

. as $dot|all($dot[];.)
[1,2,3,4,true,false,1,2,3,4,5]
false

. as $dot|all($dot[];.)
[1,2,3,4,true]
true

# Check short-circuiting
any(true, error; .)
"badness"
true

all(false, error; .)
"badness"
false

any(not)
[]
false

all(not)
[]
true

any(not)
[false]
true

all(not)
[false]
true

[any,all]
[]
[false,true]

[any,all]
[true]
[true,true]

[any,all]
[false]
[false,false]

[any,all]
[true,false]
[true,false]

[any,all]
[null,null,true]
[true,false]

#
# Paths
#

path(.foo[0,1])
null
["foo", 0]
["foo", 1]

path(.[] | select(.>3))
[1,5,3]
[1]

path(.)
42
[]

try path(.a | map(select(.b == 0))) catch .
{"a":[{"b":0}]}
"Invalid path expression with result [{\"b\":0}]"

try path(.a | map(select(.b == 0)) | .[0]) catch .
{"a":[{"b":0}]}
"Invalid path expression near attempt to access element 0 of [{\"b\":0}]"

try path(.a | map(select(.b == 0)) | .c) catch .
{"a":[{"b":0}]}
"Invalid path expression near attempt to access element \"c\" of [{\"b\":0}]"

try path(.a | map(select(.b == 0)) | .[]) catch .
{"a":[{"b":0}]}
"Invalid path expression near attempt to iterate through [{\"b\":0}]"

path(.a[path(.b)[0]])
{"a":{"b":0}}
["a","b"]

[paths]
[1,[[],{"a":2}]]
[[0],[1],[1,0],[1,1],[1,1,"a"]]

["foo",1] as $p | getpath($p), setpath($p; 20), delpaths([$p])
{"bar": 42, "foo": ["a", "b", "c", "d"]}
"b"
{"bar": 42, "foo": ["a", 20, "c", "d"]}
{"bar": 42, "foo": ["a", "c", "d"]}

map(getpath([2])), map(setpath([2]; 42)), map(delpaths([[2]]))
[[0], [0,1], [0,1,2]]
[null, null, 2]
[[0,null,42], [0,1,42], [0,1,42]]
[[0], [0,1], [0,1]]

map(delpaths([[0,"foo"]]))
[[{"foo":2, "x":1}], [{"bar":2}]]
[[{"x":1}], [{"bar":2}]]

["foo",1] as $p | getpath($p), setpath($p; 20), delpaths([$p])
{"bar":false}
null
{"bar":false, "foo": [null, 20]}
{"bar":false}

delpaths([[-200]])
[1,2,3]
[1,2,3]

try delpaths(0) catch .
{}
"Paths must be specified as an array"

del(.), del(empty), del((.foo,.bar,.baz) | .[2,3,0]), del(.foo[0], .bar[0], .foo, .baz.bar[0].x)
{"foo": [0,1,2,3,4], "bar": [0,1]}
null
{"foo": [0,1,2,3,4], "bar": [0,1]}
{"foo": [1,4], "bar": [1]}
{"bar": [1]}

del(.[1], .[-6], .[2], .[-3:9])
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
[0, 3, 5, 6, 9]

del(.[nan])
[1,2,3]
[1,2,3]

del(.[nan,nan])
[1,2,3]
[1,2,3]

# negative index
setpath([-1]; 1)
[0]
[1]

pick(.a.b.c)
null
{"a":{"b":{"c":null}}}

pick(first)
[1,2]
[1]

pick(first|first)
[[10,20],30]
[[10]]

# negative indices in path expressions (since last/1 is .[-1])
try pick(last) catch .
[1,2]
"Out of bounds negative array index"

#
# Assignment
#
.message = "goodbye"
{"message": "hello"}
{"message": "goodbye"}

.foo = .bar
{"bar":42}
{"foo":42, "bar":42}

.foo |= .+1
{"foo": 42}
{"foo": 43}

.[] += 2, .[] *= 2, .[] -= 2, .[] /= 2, .[] %=2
[1,3,5]
[3,5,7]
[2,6,10]
[-1,1,3]
[0.5, 1.5, 2.5]
[1,1,1]

[.[] % 7]
[-7,-6,-5,-4,-3,-2,-1,0,1,2,3,4,5,6,7]
[0,-6,-5,-4,-3,-2,-1,0,1,2,3,4,5,6,0]

.foo += .foo
{"foo":2}
{"foo":4}

.[0].a |= {"old":., "new":(.+1)}
[{"a":1,"b":2}]
[{"a":{"old":1, "new":2},"b":2}]

def inc(x): x |= .+1; inc(.[].a)
[{"a":1,"b":2},{"a":2,"b":4},{"a":7,"b":8}]
[{"a":2,"b":2},{"a":3,"b":4},{"a":8,"b":8}]

# #1358, getpath/1 should work in path expressions
.[] | try (getpath(["a",0,"b"]) |= 5) catch .
[null,{"b":0},{"a":0},{"a":null},{"a":[0,1]},{"a":{"b":1}},{"a":[{}]},{"a":[{"c":3}]}]
{"a":[{"b":5}]}
{"b":0,"a":[{"b":5}]}
"Cannot index number with number (0)"
{"a":[{"b":5}]}
"Cannot index number with string (\"b\")"
"Cannot index object with number (0)"
{"a":[{"b":5}]}
{"a":[{"c":3,"b":5}]}

# #2051, deletion using assigning empty against arrays
(.[] | select(. >= 2)) |= empty
[1,5,3,0,7]
[1,0]

.[] |= select(. % 2 == 0)
[0,1,2,3,4,5]
[0,2,4]

.foo[1,4,2,3] |= empty
{"foo":[0,1,2,3,4,5]}
{"foo":[0,5]}

.[2][3] = 1
[4]
[4, null, [null, null, null, 1]]

.foo[2].bar = 1
{"foo":[11], "bar":42}
{"foo":[11,null,{"bar":1}], "bar":42}

try ((map(select(.a == 1))[].b) = 10) catch .
[{"a":0},{"a":1}]
"Invalid path expression near attempt to iterate through [{\"a\":1}]"

try ((map(select(.a == 1))[].a) |= .+1) catch .
[{"a":0},{"a":1}]
"Invalid path expression near attempt to iterate through [{\"a\":1}]"

def x: .[1,2]; x=10
[0,1,2]
[0,10,10]

try (def x: reverse; x=10) catch .
[0,1,2]
"Invalid path expression with result [2,1,0]"

.[] = 1
[1,null,Infinity,-Infinity,NaN,-NaN]
[1,1,1,1,1,1]

#
# Conditionals
#

[.[] | if .foo then "yep" else "nope" end]
[{"foo":0},{"foo":1},{"foo":[]},{"foo":true},{"foo":false},{"foo":null},{"foo":"foo"},{}]
["yep","yep","yep","yep","nope","nope","yep","nope"]

[.[] | if .baz then "strange" elif .foo then "yep" else "nope" end]
[{"foo":0},{"foo":1},{"foo":[]},{"foo":true},{"foo":false},{"foo":null},{"foo":"foo"},{}]
["yep","yep","yep","yep","nope","nope","yep","nope"]

[if 1,null,2 then 3 else 4 end]
null
[3,4,3]

[if empty then 3 else 4 end]
null
[]

[if 1 then 3,4 else 5 end]
null
[3,4]

[if null then 3 else 5,6 end]
null
[5,6]

[if true then 3 end]
7
[3]

[if false then 3 end]
7
[7]

[if false then 3 else . end]
7
[7]

[if false then 3 elif false then 4 end]
7
[7]

[if false then 3 elif false then 4 else . end]
7
[7]

[-if true then 1 else 2 end]
null
[-1]

{x: if true then 1 else 2 end}
null
{"x":1}

if true then [.] else . end []
null
null

[.[] | [.foo[] // .bar]]
[{"foo":[1,2], "bar": 42}, {"foo":[1], "bar": null}, {"foo":[null,false,3], "bar": 18}, {"foo":[], "bar":42}, {"foo": [null,false,null], "bar": 41}]
[[1,2], [1], [3], [42], [41]]

.[] //= .[0]
["hello",true,false,[false],null]
["hello",true,"hello",[false],"hello"]

.[] | [.[0] and .[1], .[0] or .[1]]
[[true,[]], [false,1], [42,null], [null,false]]
[true,true]
[false,true]
[false,true]
[false,false]

[.[] | not]
[1,0,false,null,true,"hello"]
[false,false,true,true,false,false]

# Check numeric comparison binops
[10 > 0, 10 > 10, 10 > 20, 10 < 0, 10 < 10, 10 < 20]
{}
[true,false,false,false,false,true]

</pblock>

[10 >= 0, 10 >= 10, 10 >= 20, 10 <= 0, 10 <= 10, 10 <= 20]
{}
[true,true,false,false,true,true]

# And some in/equality tests
[ 10 == 10, 10 != 10, 10 != 11, 10 == 11]
{}
[true,false,true,false]

["hello" == "hello", "hello" != "hello", "hello" == "world", "hello" != "world" ]
{}
[true,false,false,true]

[[1,2,3] == [1,2,3], [1,2,3] != [1,2,3], [1,2,3] == [4,5,6], [1,2,3] != [4,5,6]]
{}
[true,false,false,true]

[{"foo":42} == {"foo":42},{"foo":42} != {"foo":42}, {"foo":42} != {"bar":42}, {"foo":42} == {"bar":42}]
{}
[true,false,true,false]

# ugly complicated thing
[{"foo":[1,2,{"bar":18},"world"]} == {"foo":[1,2,{"bar":18},"world"]},{"foo":[1,2,{"bar":18},"world"]} == {"foo":[1,2,{"bar":19},"world"]}]
{}
[true,false]

# containment operator
[("foo" | contains("foo")), ("foobar" | contains("foo")), ("foo" | contains("foobar"))]
{}
[true, true, false]

# containment operator (embedded NULs!)
[contains(""), contains("\u0000")]
"\u0000"
[true, true]

[contains(""), contains("a"), contains("ab"), contains("c"), contains("d")]
"ab\u0000cd"
[true, true, true, true, true]

[contains("cd"), contains("b\u0000"), contains("ab\u0000")]
"ab\u0000cd"
[true, true, true]

[contains("b\u0000c"), contains("b\u0000cd"), contains("b\u0000cd")]
"ab\u0000cd"
[true, true, true]

[contains("@"), contains("\u0000@"), contains("\u0000what")]
"ab\u0000cd"
[false, false, false]


# Try/catch and general `?` operator
[.[]|try if . == 0 then error("foo") elif . == 1 then .a elif . == 2 then empty else . end catch .]
[0,1,2,3]
["foo","Cannot index number with string (\"a\")",3]

[.[]|(.a, .a)?]
[null,true,{"a":1}]
[null,null,1,1]

[[.[]|[.a,.a]]?]
[null,true,{"a":1}]
[]

[if error then 1 else 2 end?]
"foo"
[]

try error(0) // 1
null
1

1, try error(2), 3
null
1
3

1 + try 2 catch 3 + 4
null
7

[-try .]
1
[-1]

try -.? catch .
"foo"
"string (\"foo\") cannot be negated"

{x: try 1, y: try error catch 2, z: if true then 3 end}
null
{"x":1,"y":2,"z":3}

{x: 1 + 2, y: false or true, z: null // 3}
null
{"x":3,"y":true,"z":3}

.[] | try error catch .
[1,null,2]
1
null
2

try error("\($__loc__)") catch .
null
"{\"file\":\"<top-level>\",\"line\":1}"

# string operations
[.[]|startswith("foo")]
["fo", "foo", "barfoo", "foobar", "barfoob"]
[false, true, false, true, false]

[.[]|endswith("foo")]
["fo", "foo", "barfoo", "foobar", "barfoob"]
[false, true, true, false, false]

[.[] | split(", ")]
["a,b, c, d, e,f",", a,b, c, d, e,f, "]
[["a,b","c","d","e,f"],["","a,b","c","d","e,f",""]]

split("")
"abc"
["a","b","c"]

[.[]|ltrimstr("foo")]
["fo", "foo", "barfoo", "foobar", "afoo"]
["fo","","barfoo","bar","afoo"]

[.[]|rtrimstr("foo")]
["fo", "foo", "barfoo", "foobar", "foob"]
["fo","","bar","foobar","foob"]

[.[]|trimstr("foo")]
["fo", "foo", "barfoo", "foobarfoo", "foob"]
["fo","","bar","bar","b"]

[.[]|ltrimstr("")]
["a", "xx", ""]
["a", "xx", ""]

[.[]|rtrimstr("")]
["a", "xx", ""]
["a", "xx", ""]

[.[]|trimstr("")]
["a", "xx", ""]
["a", "xx", ""]

[(index(","), rindex(",")), indices(",")]
"a,bc,def,ghij,klmno"
[1,13,[1,4,8,13]]

[ index("aba"), rindex("aba"), indices("aba") ]
"xababababax"
[1,7,[1,3,5,7]]

# _strindices is used by indices/1 but is callable
try _strindices("abc") catch .
123
"number (123) cannot be searched, as it is not a string"

try _strindices(123) catch .
"abc"
"number (123) is not a string"

# trim
# \u000b is vertical tab (\v not supported by json)
map(trim), map(ltrim), map(rtrim)
[" \n\t\r\f\u000b", "","  ", "a", " a ", "abc", "  abc  ", "  abc", "abc  "]
["", "", "", "a", "a", "abc", "abc", "abc", "abc"]
["", "", "", "a", "a ", "abc", "abc  ", "abc", "abc  "]
["", "", "", "a", " a", "abc", "  abc", "  abc", "abc"]

trim, ltrim, rtrim
"\u0009\u000A\u000B\u000C\u000D\u0020\u0085\u00A0\u1680\u2000\u2001\u2002\u2003\u2004\u2005\u2006\u2007\u2008\u2009\u200A\u2028\u2029\u202F\u205F\u3000abc\u0009\u000A\u000B\u000C\u000D\u0020\u0085\u00A0\u1680\u2000\u2001\u2002\u2003\u2004\u2005\u2006\u2007\u2008\u2009\u200A\u2028\u2029\u202F\u205F\u3000"
"abc"
"abc\u0009\u000A\u000B\u000C\u000D\u0020\u0085\u00A0\u1680\u2000\u2001\u2002\u2003\u2004\u2005\u2006\u2007\u2008\u2009\u200A\u2028\u2029\u202F\u205F\u3000"
"\u0009\u000A\u000B\u000C\u000D\u0020\u0085\u00A0\u1680\u2000\u2001\u2002\u2003\u2004\u2005\u2006\u2007\u2008\u2009\u200A\u2028\u2029\u202F\u205F\u3000abc"

try trim catch ., try ltrim catch ., try rtrim catch .
123
"trim input must be a string"
"trim input must be a string"
"trim input must be a string"

indices(1)
[0,1,1,2,3,4,1,5]
[1,2,6]

indices([1,2])
[0,1,2,3,1,4,2,5,1,2,6,7]
[1,8]

indices([1,2])
[1]
[]

indices(", ")
"a,b, cd,e, fgh, ijkl"
[3,9,14]

index("!")
"здравствуй мир!"
14

.[:rindex("x")]
"正xyz"
"正"

indices("o")
"🇬🇧oo"
[2,3]

indices("o")
"ƒoo"
[1,2]

[.[]|split(",")]
["a, bc, def, ghij, jklmn, a,b, c,d, e,f", "a,b,c,d, e,f,g,h"]
[["a"," bc"," def"," ghij"," jklmn"," a","b"," c","d"," e","f"],["a","b","c","d"," e","f","g","h"]]

[.[]|split(", ")]
["a, bc, def, ghij, jklmn, a,b, c,d, e,f", "a,b,c,d, e,f,g,h"]
[["a","bc","def","ghij","jklmn","a,b","c,d","e,f"],["a,b,c,d","e,f,g,h"]]

[.[] * 3]
["a", "ab", "abc"]
["aaa", "ababab", "abcabcabc"]

[.[] * "abc"]
[-1.0, -0.5, 0.0, 0.5, 1.0, 1.5, 3.7, 10.0]
[null,null,"","","abc","abc","abcabcabc","abcabcabcabcabcabcabcabcabcabc"]

[. * (nan,-nan)]
"abc"
[null,null]

. * 100000 | [.[:10],.[-10:]]
"abc"
["abcabcabca","cabcabcabc"]

. * 1000000000
""
""

try (. * 1000000000) catch .
"abc"
"Repeat string result too long"

[.[] / ","]
["a, bc, def, ghij, jklmn, a,b, c,d, e,f", "a,b,c,d, e,f,g,h"]
[["a"," bc"," def"," ghij"," jklmn"," a","b"," c","d"," e","f"],["a","b","c","d"," e","f","g","h"]]

[.[] / ", "]
["a, bc, def, ghij, jklmn, a,b, c,d, e,f", "a,b,c,d, e,f,g,h"]
[["a","bc","def","ghij","jklmn","a,b","c,d","e,f"],["a,b,c,d","e,f,g,h"]]

map(.[1] as $needle | .[0] | contains($needle))
[[[],[]], [[1,2,3], [1,2]], [[1,2,3], [3,1]], [[1,2,3], [4]], [[1,2,3], [1,4]]]
[true, true, true, false, false]

map(.[1] as $needle | .[0] | contains($needle))
[[["foobar", "foobaz"], ["baz", "bar"]], [["foobar", "foobaz"], ["foo"]], [["foobar", "foobaz"], ["blap"]]]
[true, true, false]

[({foo: 12, bar:13} | contains({foo: 12})), ({foo: 12} | contains({})), ({foo: 12, bar:13} | contains({baz:14}))]
{}
[true, true, false]

{foo: {baz: 12, blap: {bar: 13}}, bar: 14} | contains({bar: 14, foo: {blap: {}}})
{}
true

{foo: {baz: 12, blap: {bar: 13}}, bar: 14} | contains({bar: 14, foo: {blap: {bar: 14}}})
{}
false

sort
[42,[2,5,3,11],10,{"a":42,"b":2},{"a":42},true,2,[2,6],"hello",null,[2,5,6],{"a":[],"b":1},"abc","ab",[3,10],{},false,"abcd",null]
[null,null,false,true,2,10,42,"ab","abc","abcd","hello",[2,5,3,11],[2,5,6],[2,6],[3,10],{},{"a":42},{"a":42,"b":2},{"a":[],"b":1}]

(sort_by(.b) | sort_by(.a)), sort_by(.a, .b), sort_by(.b, .c), group_by(.b), group_by(.a + .b - .c == 2)
[{"a": 1, "b": 4, "c": 14}, {"a": 4, "b": 1, "c": 3}, {"a": 1, "b": 4, "c": 3}, {"a": 0, "b": 2, "c": 43}]
[{"a": 0, "b": 2, "c": 43}, {"a": 1, "b": 4, "c": 14}, {"a": 1, "b": 4, "c": 3}, {"a": 4, "b": 1, "c": 3}]
[{"a": 0, "b": 2, "c": 43}, {"a": 1, "b": 4, "c": 14}, {"a": 1, "b": 4, "c": 3}, {"a": 4, "b": 1, "c": 3}]
[{"a": 4, "b": 1, "c": 3}, {"a": 0, "b": 2, "c": 43}, {"a": 1, "b": 4, "c": 3}, {"a": 1, "b": 4, "c": 14}]
[[{"a": 4, "b": 1, "c": 3}], [{"a": 0, "b": 2, "c": 43}], [{"a": 1, "b": 4, "c": 14}, {"a": 1, "b": 4, "c": 3}]]
[[{"a": 1, "b": 4, "c": 14}, {"a": 0, "b": 2, "c": 43}], [{"a": 4, "b": 1, "c": 3}, {"a": 1, "b": 4, "c": 3}]]

unique
[1,2,5,3,5,3,1,3]
[1,2,3,5]

unique
[]
[]

[min, max, min_by(.[1]), max_by(.[1]), min_by(.[2]), max_by(.[2])]
[[4,2,"a"],[3,1,"a"],[2,4,"a"],[1,3,"a"]]
[[1,3,"a"],[4,2,"a"],[3,1,"a"],[2,4,"a"],[4,2,"a"],[1,3,"a"]]

[min,max,min_by(.),max_by(.)]
[]
[null,null,null,null]

.foo[.baz]
{"foo":{"bar":4},"baz":"bar"}
4

.[] | .error = "no, it's OK"
[{"error":true}]
{"error": "no, it's OK"}

[{a:1}] | .[] | .a=999
null
{"a": 999}

to_entries
{"a": 1, "b": 2}
[{"key":"a", "value":1}, {"key":"b", "value":2}]

from_entries
[{"key":"a", "value":1}, {"Key":"b", "Value":2}, {"name":"c", "value":3}, {"Name":"d", "Value":4}]
{"a": 1, "b": 2, "c": 3, "d": 4}

with_entries(.key |= "KEY_" + .)
{"a": 1, "b": 2}
{"KEY_a": 1, "KEY_b": 2}

map(has("foo"))
[{"foo": 42}, {}]
[true, false]

map(has(2))
[[0,1], ["a","b","c"]]
[false, true]

has(nan)
[0,1,2]
false

keys
[42,3,35]
[0,1,2]

[][.]
1000000000000000000
null

map([1,2][0:.])
[-1, 1, 2, 3, 1000000000000000000]
[[1], [1], [1,2], [1,2], [1,2]]

# Test recursive object merge

{"k": {"a": 1, "b": 2}} * .
{"k": {"a": 0,"c": 3}}
{"k": {"a": 0, "b": 2, "c": 3}}

{"k": {"a": 1, "b": 2}, "hello": {"x": 1}} * .
{"k": {"a": 0,"c": 3}, "hello": 1}
{"k": {"a": 0, "b": 2, "c": 3}, "hello": 1}

{"k": {"a": 1, "b": 2}, "hello": 1} * .
{"k": {"a": 0,"c": 3}, "hello": {"x": 1}}
{"k": {"a": 0, "b": 2, "c": 3}, "hello": {"x": 1}}

{"a": {"b": 1}, "c": {"d": 2}, "e": 5} * .
{"a": {"b": 2}, "c": {"d": 3, "f": 9}}
{"a": {"b": 2}, "c": {"d": 3, "f": 9}, "e": 5}

[.[]|arrays]
[1,2,"foo",[],[3,[]],{},true,false,null]
[[],[3,[]]]

[.[]|objects]
[1,2,"foo",[],[3,[]],{},true,false,null]
[{}]

[.[]|iterables]
[1,2,"foo",[],[3,[]],{},true,false,null]
[[],[3,[]],{}]

[.[]|scalars]
[1,2,"foo",[],[3,[]],{},true,false,null]
[1,2,"foo",true,false,null]

[.[]|values]
[1,2,"foo",[],[3,[]],{},true,false,null]
[1,2,"foo",[],[3,[]],{},true,false]

[.[]|booleans]
[1,2,"foo",[],[3,[]],{},true,false,null]
[true,false]

[.[]|nulls]
[1,2,"foo",[],[3,[]],{},true,false,null]
[null]

flatten
[0, [1], [[2]], [[[3]]]]
[0, 1, 2, 3]

flatten(0)
[0, [1], [[2]], [[[3]]]]
[0, [1], [[2]], [[[3]]]]

flatten(2)
[0, [1], [[2]], [[[3]]]]
[0, 1, 2, [3]]

flatten(2)
[0, [1, [2]], [1, [[3], 2]]]
[0, 1, 2, 1, [3], 2]

try flatten(-1) catch .
[0, [1], [[2]], [[[3]]]]
"flatten depth must not be negative"

transpose
[[1], [2,3]]
[[1,2],[null,3]]

transpose
[]
[]

ascii_upcase
"useful but not for é"
"USEFUL BUT NOT FOR é"

bsearch(0,1,2,3,4)
[1,2,3]
-1
0
1
2
-4

bsearch({x:1})
[{ "x": 0 },{ "x": 1 },{ "x": 2 }]
1

try ["OK", bsearch(0)] catch ["KO",.]
"aa"
["KO","string (\"aa\") cannot be searched from"]

strftime("%Y-%m-%dT%H:%M:%SZ")
[2015,2,5,23,51,47,4,63]
"2015-03-05T23:51:47Z"

strftime("%A, %B %d, %Y")
1435677542.822351
"Tuesday, June 30, 2015"

strftime("%Y-%m-%dT%H:%M:%SZ")
[2024,2,15]
"2024-03-15T00:00:00Z"

mktime
[2024,8,21]
1726876800

gmtime
1425599507
[2015,2,5,23,51,47,4,63]

gmtime[5]
1425599507.25
47.25

# test invalid tm input
try strftime("%Y-%m-%dT%H:%M:%SZ") catch .
["a",1,2,3,4,5,6,7]
"strftime/1 requires parsed datetime inputs"

try strflocaltime("%Y-%m-%dT%H:%M:%SZ") catch .
["a",1,2,3,4,5,6,7]
"strflocaltime/1 requires parsed datetime inputs"

try mktime catch .
["a",1,2,3,4,5,6,7]
"mktime requires parsed datetime inputs"

# oss-fuzz #67403: non-string argument with number input fails assert
try ["OK", strftime([])] catch ["KO", .]
0
["KO","strftime/1 requires a string format"]

try ["OK", strflocaltime({})] catch ["KO", .]
0
["KO","strflocaltime/1 requires a string format"]

[strptime("%Y-%m-%dT%H:%M:%SZ")|(.,mktime)]
"2015-03-05T23:51:47Z"
[[2015,2,5,23,51,47,4,63],1425599507]

# Check day-of-week and day of year computations
# (should trip an assert if this fails)
last(range(365 * 67)|("1970-03-01T01:02:03Z"|strptime("%Y-%m-%dT%H:%M:%SZ")|mktime) + (86400 * .)|strftime("%Y-%m-%dT%H:%M:%SZ")|strptime("%Y-%m-%dT%H:%M:%SZ"))
null
[2037,1,11,1,2,3,3,41]

# module system
import "a" as foo; import "b" as bar; def fooa: foo::a; [fooa, bar::a, bar::b, foo::a]
null
["a","b","c","a"]

import "c" as foo; [foo::a, foo::c]
null
[0,"acmehbah"]

include "c"; [a, c]
null
[0,"acmehbah"]

import "data" as $e; import "data" as $d; [$d[].this,$e[].that,$d::d[].this,$e::e[].that]|join(";")
null
"is a test;is too;is a test;is too"

# Regression test for #2000
import "data" as $a; import "data" as $b; def f: {$a, $b}; f
null
{"a":[{"this":"is a test","that":"is too"}],"b":[{"this":"is a test","that":"is too"}]}

include "shadow1"; e
null
2

</pblock>

include "shadow1"; include "shadow2"; e
null
3

import "shadow1" as f; import "shadow2" as f; import "shadow1" as e; [e::e, f::e]
null
[2,3]

%%FAIL
module (.+1); 0
jq: error: Module metadata must be constant at <top-level>, line 1, column 8:
    module (.+1); 0
           ^^^^^

%%FAIL
module []; 0
jq: error: Module metadata must be an object at <top-level>, line 1, column 8:
    module []; 0
           ^^

%%FAIL
include "a" (.+1); 0
jq: error: Module metadata must be constant at <top-level>, line 1, column 13:
    include "a" (.+1); 0
                ^^^^^

%%FAIL
include "a" []; 0
jq: error: Module metadata must be an object at <top-level>, line 1, column 13:
    include "a" []; 0
                ^^

%%FAIL
include "\ "; 0
jq: error: Invalid escape at line 1, column 4 (while parsing '"\ "') at <top-level>, line 1, column 10:
    include "\ "; 0
             ^^

%%FAIL
include "\(a)"; 0
jq: error: Import path must be constant at <top-level>, line 1, column 9:
    include "\(a)"; 0
            ^^^^^^

modulemeta
"c"
{"whatever":null,"deps":[{"as":"foo","is_data":false,"relpath":"a"},{"search":"./","as":"d","is_data":false,"relpath":"d"},{"search":"./","as":"d2","is_data":false,"relpath":"d"},{"search":"./../lib/jq","as":"e","is_data":false,"relpath":"e"},{"search":"./../lib/jq","as":"f","is_data":false,"relpath":"f"},{"as":"d","is_data":true,"relpath":"data"}],"defs":["a/0","c/0"]}

modulemeta | .deps | length
"c"
6

modulemeta | .defs | length
"c"
2

%%FAIL IGNORE MSG
import "syntaxerror" as e; .
jq: error: syntax error, unexpected ';', expecting end of file at tests/modules/syntaxerror/syntaxerror.jq, line 1, column 4:
    wat;
       ^

%%FAIL
%::wat
jq: error: syntax error, unexpected '%', expecting end of file at <top-level>, line 1, column 1:
    %::wat
    ^

import "test_bind_order" as check; check::check
null
true

try -. catch .
"very-long-long-long-long-string"
"string (\"very-long-long-long-long...\") cannot be negated"

try (.-.) catch .
"very-long-long-long-long-string"
"string (\"very-long-long-long-long...\") and string (\"very-long-long-long-long...\") cannot be subtracted"

"x" * range(0; 12; 2) + "☆" * 8 | try -. catch .
null
"string (\"☆☆☆☆☆☆☆☆\") cannot be negated"
"string (\"xx☆☆☆☆☆☆☆☆\") cannot be negated"
"string (\"xxxx☆☆☆☆☆☆...\") cannot be negated"
"string (\"xxxxxx☆☆☆☆☆☆...\") cannot be negated"
"string (\"xxxxxxxx☆☆☆☆☆...\") cannot be negated"
"string (\"xxxxxxxxxx☆☆☆☆...\") cannot be negated"

try (. + "x") catch . == if have_decnum then "number (12345678901234567890123456...) and string (\"x\") cannot be added" else "number (12345678901234568000000000...) and string (\"x\") cannot be added" end
123456789012345678901234567890
true

join(",")
["1",2,true,false,3.4]
"1,2,true,false,3.4"

.[] | join(",")
[[], [null], [null,null], [null,null,null]]
""
""
","
",,"

.[] | join(",")
[["a",null], [null,"a"]]
"a,"
",a"

try join(",") catch .
["1","2",{"a":{"b":{"c":33}}}]
"string (\"1,2,\") and object ({\"a\":{\"b\":{\"c\":33}}}) cannot be added"

try join(",") catch .
["1","2",[3,4,5]]
"string (\"1,2,\") and array ([3,4,5]) cannot be added"

{if:0,and:1,or:2,then:3,else:4,elif:5,end:6,as:7,def:8,reduce:9,foreach:10,try:11,catch:12,label:13,import:14,include:15,module:16}
null
{"if":0,"and":1,"or":2,"then":3,"else":4,"elif":5,"end":6,"as":7,"def":8,"reduce":9,"foreach":10,"try":11,"catch":12,"label":13,"import":14,"include":15,"module":16}

try (1/.) catch .
0
"number (1) and number (0) cannot be divided because the divisor is zero"

try (1/0) catch .
0
"number (1) and number (0) cannot be divided because the divisor is zero"

try (0/0) catch .
0
"number (0) and number (0) cannot be divided because the divisor is zero"

try (1%.) catch .
0
"number (1) and number (0) cannot be divided (remainder) because the divisor is zero"

try (1%0) catch .
0
"number (1) and number (0) cannot be divided (remainder) because the divisor is zero"

# Basic numbers tests: integers, powers of two
[range(-52;52;1)] as $powers | [$powers[]|pow(2;.)|log2|round] == $powers
null
true

[range(-99/2;99/2;1)] as $orig | [$orig[]|pow(2;.)|log2] as $back | ($orig|keys)[]|. as $k | (($orig|.[$k])-($back|.[$k]))|if . < 0 then . * -1 else . end|select(.>.00005)
null

%%FAIL
{
jq: error: syntax error, unexpected end of file at <top-level>, line 1, column 1:
    {
    ^

%%FAIL
}
jq: error: syntax error, unexpected INVALID_CHARACTER, expecting end of file at <top-level>, line 1, column 1:
    }
    ^

(.[{}] = 0)?
null

INDEX(range(5)|[., "foo\(.)"]; .[0])
null
{"0":[0,"foo0"],"1":[1,"foo1"],"2":[2,"foo2"],"3":[3,"foo3"],"4":[4,"foo4"]}

JOIN({"0":[0,"abc"],"1":[1,"bcd"],"2":[2,"def"],"3":[3,"efg"],"4":[4,"fgh"]}; .[0]|tostring)
[[5,"foo"],[3,"bar"],[1,"foobar"]]
[[[5,"foo"],null],[[3,"bar"],[3,"efg"]],[[1,"foobar"],[1,"bcd"]]]

range(5;10)|IN(range(10))
null
true
true
true
true
true

range(5;13)|IN(range(0;10;3))
null
false
true
false
false
true
false
false
false

range(10;12)|IN(range(10))
null
false
false

IN(range(10;20); range(10))
null
false

IN(range(5;20); range(10))
null
true

# Regression test for #1347
(.a as $x | .b) = "b"
{"a":null,"b":null}
{"a":null,"b":"b"}

# Regression test for #1368
(.. | select(type == "object" and has("b") and (.b | type) == "array")|.b) |= .[0]
{"a": {"b": [1, {"b": 3}]}}
{"a": {"b": 1}}

isempty(empty)
null
true

isempty(range(3))
null
false

isempty(1,error("foo"))
null
false

# Regression test for #1815
index("")
""
null

# check that dead code removal occurs after builtin it generation
builtins|length > 10
null
true

"-1"|IN(builtins[] / "/"|.[1])
null
false

all(builtins[] / "/"; .[1]|tonumber >= 0)
null
true

builtins|any(.[:1] == "_")
null
false

## Test ability to use keywords (uncomment after eval is pushed)
#(.[] as $kw | "\"{\($kw)} as $\($kw) | $\($kw) | {$\($kw)} | {\($kw):.\($kw)}\""|eval|empty),null
#["as","def","module","import","include","if","then","else","elif","end","reduce","foreach","and","or","try","catch","label","break","__loc__"]
#null
#
#(.[] as $kw | "\"def f($\($kw)): $\($kw); f(.)\""|eval|empty),null
#["as","def","module","import","include","if","then","else","elif","end","reduce","foreach","and","or","try","catch","label","break","__loc__"]
#null


#
# Tests to cover the new toliteral number functionality
# For an example see #1652 and other linked issues
#

# We are backward and sanity compatible

map(. == 1)
[1, 1.0, 1.000, 100e-2, 1e+0, 0.0001e4]
[true, true, true, true, true, true]

# When no arithmetic is involved jq should preserve the literal value

.[0] | tostring | . == if have_decnum then "13911860366432393" else "13911860366432392" end
[13911860366432393]
true

.x | tojson | . == if have_decnum then "13911860366432393" else "13911860366432392" end
{"x":13911860366432393}
true

(13911860366432393 == 13911860366432392) | . == if have_decnum then false else true end
null
true


# Applying arithmetic to the value will truncate the result to double

. - 10
13911860366432393
13911860366432382

.[0] - 10
[13911860366432393]
13911860366432382

.x - 10
{"x":13911860366432393}
13911860366432382

# Unary negation preserves numerical precision
-. | tojson == if have_decnum then "-13911860366432393" else "-13911860366432392" end
13911860366432393
true

-. | tojson == if have_decnum then "0.12345678901234567890123456789" else "0.12345678901234568" end
-0.12345678901234567890123456789
true

[1E+1000,-1E+1000 | tojson] == if have_decnum then ["1E+1000","-1E+1000"] else ["1.7976931348623157e+308","-1.7976931348623157e+308"] end
null
true

. |= try . catch .
1
1

# decnum to double conversion
.[] as $n | $n+0 | [., tostring, . == $n]
[-9007199254740993, -9007199254740992, 9007199254740992, 9007199254740993, 13911860366432393]
[-9007199254740992,"-9007199254740992",true]
[-9007199254740992,"-9007199254740992",true]
[9007199254740992,"9007199254740992",true]
[9007199254740992,"9007199254740992",true]
[13911860366432392,"13911860366432392",true]

# abs, fabs, length
abs
"abc"
"abc"

map(abs)
[-0, 0, -10, -1.1]
[0,0,10,1.1]

map(fabs)
[-0, 0, -10, -1.1]
[0,0,10,1.1]

map(abs == length) | unique
[-10, -1.1, -1e-1, 1000000000000000002]
[true]

# The following is NOT prescriptive:
map(abs)
[0.1,1000000000000000002]
[1e-1, 1000000000000000002]

[1E+1000,-1E+1000 | abs | tojson] | unique == if have_decnum then ["1E+1000"] else ["1.7976931348623157e+308"] end
null
true

[1E+1000,-1E+1000 | length | tojson] | unique == if have_decnum then ["1E+1000"] else ["1.7976931348623157e+308"] end
null
true

# Using a keyword as variable/label name

123 as $label | $label
null
123

[ label $if | range(10) | ., (select(. == 5) | break $if) ]
null
[0,1,2,3,4,5]

reduce .[] as $then (4 as $else | $else; . as $elif | . + $then * $elif)
[1,2,3]
96

1 as $foreach | 2 as $and | 3 as $or | { $foreach, $and, $or, a }
{"a":4,"b":5}
{"foreach":1,"and":2,"or":3,"a":4}

[ foreach .[] as $try (1 as $catch | $catch - 1; . + $try; .) ]
[10,9,8,7]
[10,19,27,34]


# Object construction

{ a, $__loc__, c }
{"a":[1,2,3],"b":"foo","c":{"hi":"hey"}}
{"a":[1,2,3],"__loc__":{"file":"<top-level>","line":1},"c":{"hi":"hey"}}

1 as $x | "2" as $y | "3" as $z | { $x, as, $y: 4, ($z): 5, if: 6, foo: 7 }
{"as":8}
{"x":1,"as":8,"2":4,"3":5,"if":6,"foo":7}


# nan is parsed as a valid NaN value from JSON

fromjson | isnan
"nan"
true

tojson | fromjson
{"a":nan}
{"a":null}

# NaN with payload is not parsed
.[] | try (fromjson | isnan) catch .
["NaN","-NaN","NaN1","NaN10","NaN100","NaN1000","NaN10000","NaN100000"]
true
true
"Invalid numeric literal at EOF at line 1, column 4 (while parsing 'NaN1')"
"Invalid numeric literal at EOF at line 1, column 5 (while parsing 'NaN10')"
"Invalid numeric literal at EOF at line 1, column 6 (while parsing 'NaN100')"
"Invalid numeric literal at EOF at line 1, column 7 (while parsing 'NaN1000')"
"Invalid numeric literal at EOF at line 1, column 8 (while parsing 'NaN10000')"
"Invalid numeric literal at EOF at line 1, column 9 (while parsing 'NaN100000')"

# calling input/0, or debug/0 in a test doesn't crash jq

try input catch .
null
"break"

debug
1
1

# try/catch catches more than it should #1859
"foo" | try ((try . catch "caught too much") | error) catch "caught just right"
null
"caught just right"

.[]|(try (if .=="hi" then . else error end) catch empty) | "\(.) there!"
["hi","ho"]
"hi there!"

try (["hi","ho"]|.[]|(try . catch (if .=="ho" then "BROKEN"|error else empty end)) | if .=="ho" then error else "\(.) there!" end) catch "caught outside \(.)"
null
"hi there!"
"caught outside ho"

.[]|(try . catch (if .=="ho" then "BROKEN"|error else empty end)) | if .=="ho" then error else "\(.) there!" end
["hi","ho"]
"hi there!"

try (try error catch "inner catch \(.)") catch "outer catch \(.)"
"foo"
"inner catch foo"

try ((try error catch "inner catch \(.)")|error) catch "outer catch \(.)"
"foo"
"outer catch inner catch foo"

# Also #1859, but from #1885
first(.?,.?)
null
null

# Also #1859, but from #2140
{foo: "bar"} | .foo |= .?
null
{"foo": "bar"}

# Also #1859, but from #2220
. |= try 2
1
2

. |= try 2 catch 3
1
2

.[] |= try tonumber
["1", "2a", "3", " 4", "5 ", "6.7", ".89", "-876", "+5.43", 21]
[1, 3, 6.7, 0.89, -876, 5.43, 21]

# Also 1859, but from 2073
any(keys[]|tostring?;true)
{"a":"1","b":"2","c":"3"}
true


# explode/implode
# test replacement character (65533) for outside codepoint range and 0xd800 (55296) - 0xdfff (57343) utf16 surrogate pair range
# 1.1 and 1.9 to test round down of non-ints
implode|explode
[-1,0,1,2,3,1114111,1114112,55295,55296,57343,57344,1.1,1.9]
[65533,0,1,2,3,1114111,65533,55295,65533,65533,57344,1,1]

map(try implode catch .)
[123,["a"],[nan]]
["implode input must be an array","string (\"a\") can't be imploded, unicode codepoint needs to be numeric","number (null) can't be imploded, unicode codepoint needs to be numeric"]

try 0[implode] catch .
[]
"Cannot index number with string (\"\")"

# walk
walk(.)
{"x":0}
{"x":0}

walk(1)
{"x":0}
1

# The following is a regression test, not a requirement:

</pblock>

[walk(.,1)]
{"x":0}
[{"x":0},1]

# Issue #2584
walk(select(IN({}, []) | not))
{"a":1,"b":[]}
{"a":1}

# #2815
[range(10)] | .[1.2:3.5]
null
[1,2,3]

[range(10)] | .[1.5:3.5]
null
[1,2,3]

[range(10)] | .[1.7:3.5]
null
[1,2,3]

[range(10)] | .[1.7:4294967295]
null
[1,2,3,4,5,6,7,8,9]

[range(10)] | .[1.7:-4294967296]
null
[]

[[range(10)] | .[1.1,1.5,1.7]]
null
[1,1,1]

[range(5)] | .[1.1] = 5
null
[0,5,2,3,4]

[range(3)] | .[nan:1]
null
[0]

[range(3)] | .[1:nan]
null
[1,2]

[range(3)] | .[nan]
null
null

try ([range(3)] | .[nan] = 9) catch .
null
"Cannot set array element at NaN index"

try ("foobar" | .[1.5:3.5] = "xyz") catch .
null
"Cannot update string slices"

try ([range(10)] | .[1.5:3.5] = ["xyz"]) catch .
null
[0,"xyz",4,5,6,7,8,9]

try ("foobar" | .[1.5]) catch .
null
"Cannot index string with number (1.5)"


# setpath/2 does not leak the input after an invalid get #2970

try ["ok", setpath([1]; 1)] catch ["ko", .]
{"hi":"hello"}
["ko","Cannot index object with number (1)"]

try fromjson catch .
"{'a': 123}"
"Invalid string literal; expected \", but got ' at line 1, column 5 (while parsing '{'a': 123}')"

# ltrimstr/1 rtrimstr/1 don't leak on invalid input #2977

try ltrimstr(1) catch "x", try rtrimstr(1) catch "x" | "ok"
"hi"
"ok"
"ok"

try ltrimstr("x") catch "x", try rtrimstr("x") catch "x" | "ok"
{"hey":[]}
"ok"
"ok"

# ltrimstr/1 and rtrimstr/1 return an error for non-strings. #2969

.[] as [$x, $y] | try ["ok", ($x | ltrimstr($y))] catch ["ko", .]
[["hi",1],[1,"hi"],["hi","hi"],[1,1]]
["ko","startswith() requires string inputs"]
["ko","startswith() requires string inputs"]
["ok",""]
["ko","startswith() requires string inputs"]

.[] as [$x, $y] | try ["ok", ($x | rtrimstr($y))] catch ["ko", .]
[["hi",1],[1,"hi"],["hi","hi"],[1,1]]
["ko","endswith() requires string inputs"]
["ko","endswith() requires string inputs"]
["ok",""]
["ko","endswith() requires string inputs"]


# oss-fuzz #66061: setpath/2 leaks when indexing array with array

try ["OK", setpath([[1]]; 1)] catch ["KO", .]
[]
["KO","Cannot update field at array index of array"]

# regression test for #3227
foreach .[] as $x (0, 1; . + $x)
[1, 2]
1
3
2
4

# regression test for CVE-2025-49014 (use of fmt after free)
# tests with both empty string literal and empty string created by function
# as they seems to behave reference wise differently.
strflocaltime("" | ., @uri)
0
""
""

# regression tests for #3413
# upper range bounds should be in sync with the constants defined at
#   src/jv_parse.c:#define MAX_PARSING_DEPTH (N)
#   src/jv_print.c:#define MAX_PRINT_DEPTH (N)
# (N-1)
reduce range(9999) as $_ ([];[.]) | tojson | fromjson | flatten
null
[]

# (N)
reduce range(10000) as $_ ([];[.]) | tojson | try (fromjson) catch . | (contains("<skipped: too deep>") | not) and contains("Exceeds depth limit for parsing")
null
true

# (N+1)
reduce range(10001) as $_ ([];[.]) | tojson | contains("<skipped: too deep>")
null
true

# regression test for CVE-2026-33947
setpath([range(10000) | 0]; 0) | flatten
null
[0]

try setpath([range(10001) | 0]; 0) catch .
null
"Path too deep"

getpath([range(10000) | 0])
null
null

try getpath([range(10001) | 0]) catch .
null
"Path too deep"

delpaths([[range(10000) | 0]])
null
null

try delpaths([[range(10001) | 0]]) catch .
null
"Path too deep"

# regression test for CVE-2026-40612
reduce range(10000) as $_ ([]; [.]) | contains([[]])
null
true

try (reduce range(10001) as $_ ([]; [.]) as $x | $x | contains($x)) catch .
null
"Containment check too deep"

# regression test for CVE-2026-43896
reduce range(10000) as $_ ({}; {a: .}) as $x | $x * $x | length
null
1

try (reduce range(10001) as $_ ({}; {a: .}) as $x | $x * $x) catch .
null
"Object merge too deep"

# regression test for deep structural equality recursion
try ((reduce range(10001) as $_ ([]; [.])) as $x | (reduce range(10001) as $_ ([]; [.])) as $y | $x == $y) catch .
null
"Equality check too deep"

# regression tests for deep ordering comparisons
try ((reduce range(10001) as $_ ([]; [.])) as $x | [$x, $x] | sort) catch .
null
"Comparison too deep"

try ((reduce range(10001) as $_ ([]; [.])) as $x | [$x, $x] | unique) catch .
null
"Comparison too deep"

try ((reduce range(10001) as $_ ({}; {a: .})) as $x | [$x, $x] | sort) catch .
null
"Comparison too deep"

try ((reduce range(10001) as $_ ({}; {a: .})) as $x | [$x, $x] | unique) catch .
null
"Comparison too deep"

</pblock>

%{
#include <assert.h>
#include "jv_alloc.h"
#include "compile.h"

struct lexer_param;

#include "parser.h"  /* Generated by bison. */

#define YY_USER_ACTION                           \
  do {                                           \
    yylloc->start = yyget_extra(yyscanner);      \
    yylloc->end = yylloc->start + yyleng;        \
    yyset_extra(yylloc->end, yyscanner);         \
  } while (0);

%}

%s IN_PAREN
%s IN_BRACKET
%s IN_BRACE
%s IN_QQINTERP
%x IN_QQSTRING
%x IN_COMMENT
%{
  static int enter(int opening, int state, yyscan_t yyscanner);
  static int try_exit(int closing, int state, yyscan_t yyscanner);
%}

%option noyywrap nounput noinput nodefault
%option noyyalloc noyyrealloc noyyfree
%option reentrant
%option extra-type="int"
%option bison-bridge bison-locations
%option prefix="jq_yy"
%option stack


%%

"#" { yy_push_state(IN_COMMENT, yyscanner); }
<IN_COMMENT>{
  \\(\\|\r?\n)|. { }
  \r?\n { yy_pop_state(yyscanner); }
}
<IN_COMMENT><<EOF>> { yy_pop_state(yyscanner); }

"!=" { return NEQ; }
"==" { return EQ; }
"as" { return AS; }
"import" { return IMPORT; }
"include" { return INCLUDE; }
"module" { return MODULE; }
"def" { return DEF; }
"if" { return IF; }
"then" { return THEN; }
"else" { return ELSE; }
"elif" { return ELSE_IF; }
"and" { return AND; }
"or" { return OR; }
"end" { return END; }
"reduce" { return REDUCE; }
"foreach" { return FOREACH; }
"//" { return DEFINEDOR; }
"try" { return TRY; }
"catch" { return CATCH; }
"label" { return LABEL; }
"break" { return BREAK; }
"$__loc__" { return LOC; }
"|=" { return SETPIPE; }
"+=" { return SETPLUS; }
"-=" { return SETMINUS; }
"*=" { return SETMULT; }
"/=" { return SETDIV; }
"%=" { return SETMOD; }
"//=" { return SETDEFINEDOR; }
"<=" { return LESSEQ; }
">=" { return GREATEREQ; }
".." { return REC; }
"?//" { return ALTERNATION; }
"."|"?"|"="|";"|","|":"|"|"|"+"|"-"|"*"|"/"|"%"|"\$"|"<"|">" { return yytext[0];}

"["|"{"|"(" {
  return enter(yytext[0], YY_START, yyscanner);
}

"]"|"}"|")" {
  return try_exit(yytext[0], YY_START, yyscanner);
}

"@"[a-zA-Z0-9_]+ {
  yylval->literal = jv_string_sized(yytext + 1, yyleng - 1); return FORMAT;
}

([0-9]+(\.[0-9]*)?|\.[0-9]+)([eE][+-]?[0-9]+)? {
   yylval->literal = jv_parse_sized(yytext, yyleng); return LITERAL;
}

"\"" {
  yy_push_state(IN_QQSTRING, yyscanner);
  return QQSTRING_START;
}

<IN_QQSTRING>{
  "\\(" {
    return enter(QQSTRING_INTERP_START, YY_START, yyscanner);
  }
  "\"" {
    yy_pop_state(yyscanner);
    return QQSTRING_END;
  }
  (\\[^u(]|\\u[a-zA-Z0-9]{0,4})+ {
    /* pass escapes to the json parser */
    jv escapes = jv_string_fmt("\"%.*s\"", (int)yyleng, yytext);
    yylval->literal = jv_parse_sized(jv_string_value(escapes), jv_string_length_bytes(jv_copy(escapes)));
    jv_free(escapes);
    return QQSTRING_TEXT;
  }
  [^\\\"]+ {
    yylval->literal = jv_string_sized(yytext, yyleng);
    return QQSTRING_TEXT;
  }
  . {
    return INVALID_CHARACTER;
  }
}


([a-zA-Z_][a-zA-Z_0-9]*::)*[a-zA-Z_][a-zA-Z_0-9]*  { yylval->literal = jv_string(yytext); return IDENT;}
\.[a-zA-Z_][a-zA-Z_0-9]*  { yylval->literal = jv_string(yytext+1); return FIELD;}
\$([a-zA-Z_][a-zA-Z_0-9]*::)*[a-zA-Z_][a-zA-Z_0-9]*  { yylval->literal = jv_string(yytext+1); return BINDING;}

[ \r\n\t]+  {}

. { return INVALID_CHARACTER; }

%%
/* perhaps these should be calls... */
/*
"true" { return TRUE; }
"false" { return FALSE; }
"null" { return NULL; }
*/
static int try_exit(int c, int state, yyscan_t yyscanner) {
  char match = 0;
  int ret;
  switch (state) {
  case IN_PAREN: match = ret = ')'; break;
  case IN_BRACKET: match = ret = ']'; break;
  case IN_BRACE: match = ret = '}'; break;

  case IN_QQINTERP:
    match = ')';
    ret = QQSTRING_INTERP_END;
    break;

  default:
    // may not be the best error to give
    return INVALID_CHARACTER;
  }
  assert(match);
  if (match == c) {
    yy_pop_state(yyscanner);
    return ret;
  } else {
    // FIXME: should we pop? Give a better error at least
    return INVALID_CHARACTER;
  }
}

static int enter(int c, int currstate, yyscan_t yyscanner) {
  int state = 0;
  switch (c) {
  case '(': state = IN_PAREN; break;
  case '[': state = IN_BRACKET; break;
  case '{': state = IN_BRACE; break;
  case QQSTRING_INTERP_START: state = IN_QQINTERP; break;
  }
  assert(state);
  yy_push_state(state, yyscanner);
  return c;
}

void* yyalloc(size_t sz, void* extra) {
  return jv_mem_alloc(sz);
}
void* yyrealloc(void* p, size_t sz, void* extra) {
  return jv_mem_realloc(p, sz);
}
void yyfree(void* p, void* extra) {
  jv_mem_free(p);
}

</pblock>

%{
#include <assert.h>
#include <math.h>
#include <stdio.h>
#include <string.h>
#include "compile.h"
#include "jv_alloc.h"
#include "builtin.h"
#define YYMALLOC jv_mem_alloc
#define YYFREE jv_mem_free
%}
%code requires {
#include "locfile.h"
struct lexer_param;

#define YYLTYPE location
#define YYLLOC_DEFAULT(Loc, Rhs, N)             \
  do {                                          \
    if (N) {                                    \
      (Loc).start = YYRHSLOC(Rhs, 1).start;     \
      (Loc).end = YYRHSLOC(Rhs, N).end;         \
    } else {                                    \
      (Loc).start = YYRHSLOC(Rhs, 0).end;       \
      (Loc).end = YYRHSLOC(Rhs, 0).end;         \
    }                                           \
  } while (0)
}

%locations
%define parse.error verbose
%define api.pure
%union {
  jv literal;
  block blk;
}

%destructor { jv_free($$); } <literal>
%destructor { block_free($$); } <blk>

%parse-param {block* answer}
%parse-param {int* errors}
%parse-param {struct locfile* locations}
%parse-param {struct lexer_param* lexer_param_ptr}
%lex-param {block* answer}
%lex-param {int* errors}
%lex-param {struct locfile* locations}
%lex-param {struct lexer_param* lexer_param_ptr}


%token INVALID_CHARACTER
%token <literal> IDENT
%token <literal> FIELD
%token <literal> BINDING
%token <literal> LITERAL
%token <literal> FORMAT
%token REC ".."
%token SETMOD "%="
%token EQ "=="
%token NEQ "!="
%token DEFINEDOR "//"
%token AS "as"
%token DEF "def"
%token MODULE "module"
%token IMPORT "import"
%token INCLUDE "include"
%token IF "if"
%token THEN "then"
%token ELSE "else"
%token ELSE_IF "elif"
%token REDUCE "reduce"
%token FOREACH "foreach"
%token END "end"
%token AND "and"
%token OR "or"
%token TRY "try"
%token CATCH "catch"
%token LABEL "label"
%token BREAK "break"
%token LOC "$__loc__"
%token SETPIPE "|="
%token SETPLUS "+="
%token SETMINUS "-="
%token SETMULT "*="
%token SETDIV "/="
%token SETDEFINEDOR "//="
%token LESSEQ "<="
%token GREATEREQ ">="
%token ALTERNATION "?//"

%token QQSTRING_START
%token <literal> QQSTRING_TEXT
%token QQSTRING_INTERP_START
%token QQSTRING_INTERP_END
%token QQSTRING_END

/* Instead of raising this, find a way to use precedence to resolve
 * shift-reduce conflicts. */
%expect 0

%precedence FUNCDEF
%right '|'
%left ','
%right "//"
%nonassoc '=' SETPIPE SETPLUS SETMINUS SETMULT SETDIV SETMOD SETDEFINEDOR
%left OR
%left AND
%nonassoc NEQ EQ '<' '>' LESSEQ GREATEREQ
%left '+' '-'
%left '*' '/' '%'
%precedence NONOPT /* non-optional; rules for which a specialized
                      '?' rule should be preferred over Expr '?' */
%precedence '?' '.' '[' FIELD
%precedence "try"
%precedence "catch"


%type <blk> Query Expr Term
%type <blk> DictPairs DictPair DictExpr
%type <blk> ElseBody
%type <blk> String QQString
%type <blk> FuncDef FuncDefs
%type <blk> Module Import Imports ImportWhat ImportFrom
%type <blk> Param Params Arg Args
%type <blk> Patterns RepPatterns Pattern ArrayPats ObjPats ObjPat
%type <literal> Keyword
%type <literal> StringStart
%{
#include "lexer.h"
struct lexer_param {
  yyscan_t lexer;
};
#define FAIL(loc, msg)                                             \
  do {                                                             \
    location l = loc;                                              \
    yyerror(&l, answer, errors, locations, lexer_param_ptr, msg);  \
    /*YYERROR*/;                                                   \
  } while (0)

void yyerror(YYLTYPE* loc, block* answer, int* errors,
             struct locfile* locations, struct lexer_param* lexer_param_ptr, const char *s){
  (*errors)++;
  locfile_locate(locations, *loc, "jq: error: %s", s);
}

int yylex(YYSTYPE* yylval, YYLTYPE* yylloc, block* answer, int* errors,
          struct locfile* locations, struct lexer_param* lexer_param_ptr) {
  yyscan_t lexer = lexer_param_ptr->lexer;
  int tok = jq_yylex(yylval, yylloc, lexer);
  if ((tok == LITERAL || tok == QQSTRING_TEXT) && !jv_is_valid(yylval->literal)) {
    jv msg = jv_invalid_get_msg(jv_copy(yylval->literal));
    if (jv_get_kind(msg) == JV_KIND_STRING) {
      FAIL(*yylloc, jv_string_value(msg));
    } else {
      FAIL(*yylloc, "Invalid literal");
    }
    jv_free(msg);
    jv_free(yylval->literal);
    yylval->literal = jv_null();
  }
  return tok;
}

/* Returns string message if the block is a constant that is not valid as an
 * object key. */
static jv check_object_key(block k) {
  if (block_is_const(k) && block_const_kind(k) != JV_KIND_STRING) {
    char errbuf[30];
    return jv_string_fmt("Cannot use %s (%s) as object key",
        jv_kind_name(block_const_kind(k)),
        jv_dump_string_trunc(block_const(k), errbuf, sizeof(errbuf)));
  }
  return jv_invalid();
}

static block gen_index(block obj, block key) {
  return BLOCK(gen_subexp(key), obj, gen_op_simple(INDEX));
}

static block gen_index_opt(block obj, block key) {
  return BLOCK(gen_subexp(key), obj, gen_op_simple(INDEX_OPT));
}

static block gen_slice_index(block obj, block start, block end, opcode idx_op) {
  block key = BLOCK(gen_subexp(gen_const(jv_object())),
                    gen_subexp(gen_const(jv_string("start"))),
                    gen_subexp(start),
                    gen_op_simple(INSERT),
                    gen_subexp(gen_const(jv_string("end"))),
                    gen_subexp(end),
                    gen_op_simple(INSERT));
  return BLOCK(key, obj, gen_op_simple(idx_op));
}

static block constant_fold(block a, block b, int op) {
  if (!block_is_single(a) || !block_is_const(a) ||
      !block_is_single(b) || !block_is_const(b))
    return gen_noop();

  jv jv_a = block_const(a);
  block_free(a);
  jv jv_b = block_const(b);
  block_free(b);

  jv res = jv_invalid();
  switch (op) {
  case '+': res = binop_plus(jv_a, jv_b); break;
  case '-': res = binop_minus(jv_a, jv_b); break;
  case '*': res = binop_multiply(jv_a, jv_b); break;
  case '/': res = binop_divide(jv_a, jv_b); break;
  case '%': res = binop_mod(jv_a, jv_b); break;
  case EQ: res = binop_equal(jv_a, jv_b); break;
  case NEQ: res = binop_notequal(jv_a, jv_b); break;
  case '<': res = binop_less(jv_a, jv_b); break;
  case '>': res = binop_greater(jv_a, jv_b); break;
  case LESSEQ: res = binop_lesseq(jv_a, jv_b); break;
  case GREATEREQ: res = binop_greatereq(jv_a, jv_b); break;
  }

  if (jv_is_valid(res))
    return gen_const(res);

  return gen_error(jv_invalid_get_msg(res));
}

static block gen_binop(block a, block b, int op) {
  block folded = constant_fold(a, b, op);
  if (!block_is_noop(folded))
    return folded;

  const char* funcname = 0;
  switch (op) {
  case '+': funcname = "_plus"; break;
  case '-': funcname = "_minus"; break;
  case '*': funcname = "_multiply"; break;
  case '/': funcname = "_divide"; break;
  case '%': funcname = "_mod"; break;
  case EQ: funcname = "_equal"; break;
  case NEQ: funcname = "_notequal"; break;
  case '<': funcname = "_less"; break;
  case '>': funcname = "_greater"; break;
  case LESSEQ: funcname = "_lesseq"; break;
  case GREATEREQ: funcname = "_greatereq"; break;
  }
  assert(funcname);

  return gen_call(funcname, BLOCK(gen_lambda(a), gen_lambda(b)));
}

static block gen_format(block a, jv fmt) {
  return BLOCK(a, gen_call("format", gen_lambda(gen_const(fmt))));
}

static block gen_definedor_assign(block object, block val) {
  block tmp = gen_op_var_fresh(STOREV, "tmp");
  return BLOCK(gen_op_simple(DUP),
               val, tmp,
               gen_call("_modify", BLOCK(gen_lambda(object),
                                         gen_lambda(gen_definedor(gen_noop(),
                                                                  gen_op_bound(LOADV, tmp))))));
}

static block gen_update(block object, block val, int optype) {
  block tmp = gen_op_var_fresh(STOREV, "tmp");
  return BLOCK(gen_op_simple(DUP),
               val,
               tmp,
               gen_call("_modify", BLOCK(gen_lambda(object),
                                         gen_lambda(gen_binop(gen_noop(),
                                                              gen_op_bound(LOADV, tmp),
                                                              optype)))));
}

static block gen_loc_object(location *loc, struct locfile *locations) {
  return gen_const(JV_OBJECT(jv_string("file"), jv_copy(locations->fname),
                             jv_string("line"), jv_number(locfile_get_line(locations, loc->start) + 1)));
}

%}

%%
TopLevel:
Module Imports Query {
  *answer = BLOCK($1, $2, gen_op_simple(TOP), $3);
} |
Module Imports FuncDefs {
  *answer = BLOCK($1, $2, $3);
}

Module:
%empty {
  $$ = gen_noop();
} |
"module" Query ';' {
  if (!block_is_const($2)) {
    FAIL(@2, "Module metadata must be constant");
    $$ = gen_noop();
    block_free($2);
  } else if (block_const_kind($2) != JV_KIND_OBJECT) {
    FAIL(@2, "Module metadata must be an object");
    $$ = gen_noop();
    block_free($2);
  } else {
    $$ = gen_module($2);
  }
}

Imports:
%empty {
  $$ = gen_noop();
} |
Import Imports {
  $$ = BLOCK($1, $2);
}

FuncDefs:
%empty {
  $$ = gen_noop();
} |
FuncDef FuncDefs {
  $$ = block_join($1, $2);
}


Query:
FuncDef Query %prec FUNCDEF {
  $$ = block_bind_referenced($1, $2, OP_IS_CALL_PSEUDO);
} |
Expr "as" Patterns '|' Query {
  $$ = gen_destructure($1, $3, $5);
} |
"label" BINDING '|' Query {
  jv v = jv_string_fmt("*label-%s", jv_string_value($2));
  $$ = gen_location(@$, locations, gen_label(jv_string_value(v), $4));
  jv_free($2);
  jv_free(v);
} |
Query '|' Query {
  $$ = block_join($1, $3);
} |
Query ',' Query {
  $$ = gen_both($1, $3);
} |
Expr {
  $$ = $1;
}


Expr:
Expr "//" Expr {
  $$ = gen_definedor($1, $3);
} |
Expr '=' Expr {
  $$ = gen_call("_assign", BLOCK(gen_lambda($1), gen_lambda($3)));
} |
Expr "or" Expr {
  $$ = gen_or($1, $3);
} |
Expr "and" Expr {
  $$ = gen_and($1, $3);
} |
Expr "//=" Expr {
  $$ = gen_definedor_assign($1, $3);
} |
Expr "|=" Expr {
  $$ = gen_call("_modify", BLOCK(gen_lambda($1), gen_lambda($3)));
} |
Expr '+' Expr {
  $$ = gen_binop($1, $3, '+');
} |
Expr "+=" Expr {
  $$ = gen_update($1, $3, '+');
} |
Expr '-' Expr {
  $$ = gen_binop($1, $3, '-');
} |
Expr "-=" Expr {
  $$ = gen_update($1, $3, '-');
} |
Expr '*' Expr {
  $$ = gen_binop($1, $3, '*');
} |
Expr "*=" Expr {
  $$ = gen_update($1, $3, '*');
} |
Expr '/' Expr {
  $$ = gen_binop($1, $3, '/');
} |
Expr '%' Expr {
  $$ = gen_binop($1, $3, '%');
} |
Expr "/=" Expr {
  $$ = gen_update($1, $3, '/');
} |
Expr SETMOD Expr {
  $$ = gen_update($1, $3, '%');
} |
Expr "==" Expr {
  $$ = gen_binop($1, $3, EQ);
} |
Expr "!=" Expr {
  $$ = gen_binop($1, $3, NEQ);
} |
Expr '<' Expr {
  $$ = gen_binop($1, $3, '<');
} |
Expr '>' Expr {
  $$ = gen_binop($1, $3, '>');
} |
Expr "<=" Expr {
  $$ = gen_binop($1, $3, LESSEQ);
} |
Expr ">=" Expr {
  $$ = gen_binop($1, $3, GREATEREQ);
} |
Term %prec NONOPT {
  $$ = $1;
}


Import:
ImportWhat ';' {
  $$ = $1;
} |
ImportWhat Query ';' {
  if (!block_is_const($2)) {
    FAIL(@2, "Module metadata must be constant");
    $$ = gen_noop();
    block_free($1);
    block_free($2);
  } else if (block_const_kind($2) != JV_KIND_OBJECT) {
    FAIL(@2, "Module metadata must be an object");
    $$ = gen_noop();
    block_free($1);
    block_free($2);
  } else {
    $$ = gen_import_meta($1, $2);
  }
}

ImportWhat:
"import" ImportFrom "as" BINDING {
  $$ = gen_import(block_const($2), $4, 1);
  block_free($2);
} |
"import" ImportFrom "as" IDENT {
  $$ = gen_import(block_const($2), $4, 0);
  block_free($2);
} |
"include" ImportFrom {
  $$ = gen_import(block_const($2), jv_invalid(), 0);
  block_free($2);
}

ImportFrom:
String {
  if (!block_is_const($1)) {
    FAIL(@1, "Import path must be constant");
    $$ = gen_const(jv_string(""));
    block_free($1);
  } else {
    $$ = $1;
  }
}

FuncDef:
"def" IDENT ':' Query ';' {
  $$ = gen_function(jv_string_value($2), gen_noop(), $4);
  jv_free($2);
} |

"def" IDENT '(' Params ')' ':' Query ';' {
  $$ = gen_function(jv_string_value($2), $4, $7);
  jv_free($2);
}

</pblock>

Params:
Param {
  $$ = $1;
} |
Params ';' Param {
  $$ = BLOCK($1, $3);
}

Param:
BINDING {
  $$ = gen_param_regular(jv_string_value($1));
  jv_free($1);
} |
IDENT {
  $$ = gen_param(jv_string_value($1));
  jv_free($1);
}


StringStart:
FORMAT QQSTRING_START {
  $$ = $1;
} |
QQSTRING_START {
  $$ = jv_string("text");
}


String:
StringStart QQString QQSTRING_END {
  $$ = $2;
  jv_free($1);
};


QQString:
%empty {
  $$ = gen_const(jv_string(""));
} |
QQString QQSTRING_TEXT {
  $$ = gen_binop($1, gen_const($2), '+');
} |
QQString QQSTRING_INTERP_START Query QQSTRING_INTERP_END {
  $$ = gen_binop($1, gen_format($3, jv_copy($<literal>0)), '+');
}


ElseBody:
"elif" Query "then" Query ElseBody {
  $$ = gen_cond($2, $4, $5);
} |
"else" Query "end" {
  $$ = $2;
} |
"end" {
  $$ = gen_noop();
}


Term:
'.' {
  $$ = gen_noop();
} |
REC {
  $$ = gen_call("recurse", gen_noop());
} |
BREAK BINDING {
  jv v = jv_string_fmt("*label-%s", jv_string_value($2));     // impossible symbol
  $$ = gen_location(@$, locations,
                    BLOCK(gen_op_unbound(LOADV, jv_string_value(v)),
                    gen_call("error", gen_noop())));
  jv_free(v);
  jv_free($2);
} |
BREAK error {
  FAIL(@$, "break requires a label to break to");
  $$ = gen_noop();
} |
Term FIELD '?' {
  $$ = gen_index_opt($1, gen_const($2));
} |
FIELD '?' {
  $$ = gen_index_opt(gen_noop(), gen_const($1));
} |
Term '.' String '?' {
  $$ = gen_index_opt($1, $3);
} |
'.' String '?' {
  $$ = gen_index_opt(gen_noop(), $2);
} |
Term FIELD %prec NONOPT {
  $$ = gen_index($1, gen_const($2));
} |
FIELD %prec NONOPT {
  $$ = gen_index(gen_noop(), gen_const($1));
} |
Term '.' String %prec NONOPT {
  $$ = gen_index($1, $3);
} |
'.' String %prec NONOPT {
  $$ = gen_index(gen_noop(), $2);
} |
'.' error {
  FAIL(@$, "try .[\"field\"] instead of .field for unusually named fields");
  $$ = gen_noop();
} |
'.' IDENT error {
  jv_free($2);
  FAIL(@$, "try .[\"field\"] instead of .field for unusually named fields");
  $$ = gen_noop();
} |
/* FIXME: string literals */
Term '[' Query ']' '?' {
  $$ = gen_index_opt($1, $3);
} |
Term '[' Query ']' %prec NONOPT {
  $$ = gen_index($1, $3);
} |
Term '.' '[' Query ']' '?' {
  $$ = gen_index_opt($1, $4);
} |
Term '.' '[' Query ']' %prec NONOPT {
  $$ = gen_index($1, $4);
} |
Term '[' ']' '?' {
  $$ = block_join($1, gen_op_simple(EACH_OPT));
} |
Term '[' ']' %prec NONOPT {
  $$ = block_join($1, gen_op_simple(EACH));
} |
Term '.' '[' ']' '?' {
  $$ = block_join($1, gen_op_simple(EACH_OPT));
} |
Term '.' '[' ']' %prec NONOPT {
  $$ = block_join($1, gen_op_simple(EACH));
} |
Term '[' Query ':' Query ']' '?' {
  $$ = gen_slice_index($1, $3, $5, INDEX_OPT);
} |
Term '[' Query ':' ']' '?' {
  $$ = gen_slice_index($1, $3, gen_const(jv_null()), INDEX_OPT);
} |
Term '[' ':' Query ']' '?' {
  $$ = gen_slice_index($1, gen_const(jv_null()), $4, INDEX_OPT);
} |
Term '[' Query ':' Query ']' %prec NONOPT {
  $$ = gen_slice_index($1, $3, $5, INDEX);
} |
Term '[' Query ':' ']' %prec NONOPT {
  $$ = gen_slice_index($1, $3, gen_const(jv_null()), INDEX);
} |
Term '[' ':' Query ']' %prec NONOPT {
  $$ = gen_slice_index($1, gen_const(jv_null()), $4, INDEX);
} |
Term '?' {
  $$ = gen_try($1, gen_op_simple(BACKTRACK));
} |
LITERAL {
  $$ = gen_const($1);
} |
String {
  $$ = $1;
} |
FORMAT {
  $$ = gen_format(gen_noop(), $1);
} |
'-' Term {
  $$ = BLOCK($2, gen_call("_negate", gen_noop()));
} |
'(' Query ')' {
  $$ = $2;
} |
'[' Query ']' {
  $$ = gen_collect($2);
} |
'[' ']' {
  $$ = gen_const(jv_array());
} |
'{' DictPairs '}' {
  block o = gen_const_object($2);
  if (o.first != NULL)
    $$ = o;
  else
    $$ = BLOCK(gen_subexp(gen_const(jv_object())), $2, gen_op_simple(POP));
} |
"reduce" Expr "as" Patterns '(' Query ';' Query ')' {
  $$ = gen_reduce($2, $4, $6, $8);
} |
"foreach" Expr "as" Patterns '(' Query ';' Query ';' Query ')' {
  $$ = gen_foreach($2, $4, $6, $8, $10);
} |
"foreach" Expr "as" Patterns '(' Query ';' Query ')' {
  $$ = gen_foreach($2, $4, $6, $8, gen_noop());
} |
"if" Query "then" Query ElseBody {
  $$ = gen_cond($2, $4, $5);
} |
"if" Query "then" error {
  FAIL(@$, "Possibly unterminated 'if' statement");
  $$ = $2;
} |
"try" Expr "catch" Expr {
  $$ = gen_try($2, $4);
} |
"try" Expr "catch" error {
  FAIL(@$, "Possibly unterminated 'try' statement");
  $$ = $2;
} |
"try" Expr {
  $$ = gen_try($2, gen_op_simple(BACKTRACK));
} |
/*
 * This `$$$$varname` hack is strictly private to jq builtins.  DO NOT USE!!
 *
 * This is used in `_modify`, in src/builtin.jq, to avoid holding on to a
 * reference to `.`.
 *
 * We could just have the compiler emit bytecode for `_modify` so it can use
 * LOADVN w/o needing jq syntax for LOADVN.
 *
 * This syntax, `$$$$varname`, violates referential transparency: it has
 * side-effects that are surprising.
 *
 * DO NOT USE!!  I will break your jq code if you do use this outside
 * src/builtin.jq.
 */
'$' '$' '$' BINDING {
  $$ = gen_location(@$, locations, gen_op_unbound(LOADVN, jv_string_value($4)));
  jv_free($4);
} |
BINDING {
  $$ = gen_location(@$, locations, gen_op_unbound(LOADV, jv_string_value($1)));
  jv_free($1);
} |
"$__loc__" {
  $$ = gen_loc_object(&@$, locations);
} |
IDENT {
  const char *s = jv_string_value($1);
  if (strcmp(s, "false") == 0)
    $$ = gen_const(jv_false());
  else if (strcmp(s, "true") == 0)
    $$ = gen_const(jv_true());
  else if (strcmp(s, "null") == 0)
    $$ = gen_const(jv_null());
  else
    $$ = gen_location(@$, locations, gen_call(s, gen_noop()));
  jv_free($1);
} |
IDENT '(' Args ')' {
  $$ = gen_call(jv_string_value($1), $3);
  $$ = gen_location(@1, locations, $$);
  jv_free($1);
} |
'(' error ')' { $$ = gen_noop(); } |
'[' error ']' { $$ = gen_noop(); } |
Term '[' error ']' { $$ = $1; } |
'{' error '}' { $$ = gen_noop(); }

Args:
Arg {
  $$ = $1;
} |
Args ';' Arg {
  $$ = BLOCK($1, $3);
}

Arg:
Query {
  $$ = gen_lambda($1);
}

RepPatterns:
RepPatterns "?//" Pattern {
  $$ = BLOCK($1, gen_destructure_alt($3));
} |
Pattern {
  $$ = gen_destructure_alt($1);
}

Patterns:
RepPatterns "?//" Pattern {
  $$ = BLOCK($1, $3);
} |
Pattern {
  $$ = $1;
}

Pattern:
BINDING {
  $$ = gen_op_unbound(STOREV, jv_string_value($1));
  jv_free($1);
} |
'[' ArrayPats ']' {
  $$ = BLOCK($2, gen_op_simple(POP));
} |
'{' ObjPats '}' {
  $$ = BLOCK($2, gen_op_simple(POP));
}

ArrayPats:
Pattern {
  $$ = gen_array_matcher(gen_noop(), $1);
} |
ArrayPats ',' Pattern {
  $$ = gen_array_matcher($1, $3);
}

ObjPats:
ObjPat {
  $$ = $1;
} |
ObjPats ',' ObjPat {
  $$ = BLOCK($1, $3);
}

ObjPat:
BINDING {
  $$ = gen_object_matcher(gen_const($1), gen_op_unbound(STOREV, jv_string_value($1)));
} |
BINDING ':' Pattern {
  $$ = gen_object_matcher(gen_const($1), BLOCK(gen_op_simple(DUP), gen_op_unbound(STOREV, jv_string_value($1)), $3));
} |
IDENT ':' Pattern {
  $$ = gen_object_matcher(gen_const($1), $3);
} |
Keyword ':' Pattern {
  $$ = gen_object_matcher(gen_const($1), $3);
} |
String ':' Pattern {
  $$ = gen_object_matcher($1, $3);
} |
'(' Query ')' ':' Pattern {
  jv msg = check_object_key($2);
  if (jv_is_valid(msg)) {
    FAIL(@2, jv_string_value(msg));
  }
  jv_free(msg);
  $$ = gen_object_matcher($2, $5);
} |
error ':' Pattern {
  FAIL(@$, "May need parentheses around object key expression");
  $$ = $3;
}

Keyword:
"as" {
  $$ = jv_string("as");
} |
"def" {
  $$ = jv_string("def");
} |
"module" {
  $$ = jv_string("module");
} |
"import" {
  $$ = jv_string("import");
} |
"include" {
  $$ = jv_string("include");
} |
"if" {
  $$ = jv_string("if");
} |
"then" {
  $$ = jv_string("then");
} |
"else" {
  $$ = jv_string("else");
} |
"elif" {
  $$ = jv_string("elif");
} |
"reduce" {
  $$ = jv_string("reduce");
} |
"foreach" {
  $$ = jv_string("foreach");
} |
"end" {
  $$ = jv_string("end");
} |
"and" {
  $$ = jv_string("and");
} |
"or" {
  $$ = jv_string("or");
} |
"try" {
  $$ = jv_string("try");
} |
"catch" {
  $$ = jv_string("catch");
} |
"label" {
  $$ = jv_string("label");
} |
"break" {
  $$ = jv_string("break");
}


DictPairs:
%empty {
  $$ = gen_noop();
} |
DictPair {
  $$ = $1;
} |
DictPair ',' DictPairs {
  $$ = block_join($1, $3);
}

DictPair:
IDENT ':' DictExpr {
  $$ = gen_dictpair(gen_const($1), $3);
} |
Keyword ':' DictExpr {
  $$ = gen_dictpair(gen_const($1), $3);
} |
String ':' DictExpr {
  $$ = gen_dictpair($1, $3);
} |
String {
  $$ = gen_dictpair($1, BLOCK(gen_op_simple(POP), gen_op_simple(DUP2),
                              gen_op_simple(DUP2), gen_op_simple(INDEX)));
} |
BINDING ':' DictExpr {
  $$ = gen_dictpair(gen_location(@$, locations, gen_op_unbound(LOADV, jv_string_value($1))),
                    $3);
  jv_free($1);
} |
BINDING {
  $$ = gen_dictpair(gen_const($1),
                    gen_location(@$, locations, gen_op_unbound(LOADV, jv_string_value($1))));
} |
IDENT {
  $$ = gen_dictpair(gen_const(jv_copy($1)),
                    gen_index(gen_noop(), gen_const($1)));
} |
"$__loc__" {
  $$ = gen_dictpair(gen_const(jv_string("__loc__")),
                    gen_loc_object(&@$, locations));
} |
Keyword {
  $$ = gen_dictpair(gen_const(jv_copy($1)),
                    gen_index(gen_noop(), gen_const($1)));
} |
'(' Query ')' ':' DictExpr {
  jv msg = check_object_key($2);
  if (jv_is_valid(msg)) {
    FAIL(@2, jv_string_value(msg));
  }
  jv_free(msg);
  $$ = gen_dictpair($2, $5);
} |
error ':' DictExpr {
  FAIL(@1, "May need parentheses around object key expression");
  $$ = $3;
}

DictExpr:
DictExpr '|' DictExpr {
  $$ = block_join($1, $3);
} |
Expr {
  $$ = $1;
}
%%

int jq_parse(struct locfile* locations, block* answer) {
  struct lexer_param scanner;
  YY_BUFFER_STATE buf;
  jq_yylex_init_extra(0, &scanner.lexer);
  buf = jq_yy_scan_bytes(locations->data, locations->length, scanner.lexer);
  int errors = 0;
  *answer = gen_noop();
  yyparse(answer, &errors, locations, &scanner);
  jq_yy_delete_buffer(buf, scanner.lexer);
  jq_yylex_destroy(scanner.lexer);
  if (errors > 0) {
    block_free(*answer);
    *answer = gen_noop();
  }
  return errors;
}

int jq_parse_library(struct locfile* locations, block* answer) {
  int errs = jq_parse(locations, answer);
  if (errs) return errs;
  if (block_has_main(*answer)) {
    locfile_locate(locations, UNKNOWN_LOCATION, "jq: error: library should only have function definitions, not a main expression");
    return 1;
  }
  assert(block_has_only_binders_and_imports(*answer, OP_IS_CALL_PSEUDO));
  return 0;
}

</pblock>

#!/usr/bin/env python3
"""Run the upstream jq conformance corpus against a candidate implementation.

This is the scoring instrument. It is supplied, not authored: it is staged verbatim into the
build directory, hash-verified against the import, and restored before grading. Its exit status
is the acceptance verdict.

It is deliberately external to the implementation. Upstream jq grades itself, through its own
``--run-tests`` flag; a self-graded suite proves nothing here, so this runner re-implements the
corpus protocol and drives the candidate as a subprocess, one process per case.

Imported sources land in ``sources/`` inside the application directory, so this is normally
invoked as ``python3 sources/run_conformance.py`` from that directory.

Usage:
    JQ=./jq python3 sources/run_conformance.py                     # full corpus, the scored run
    JQ=./jq python3 sources/run_conformance.py -v                  # list passing cases too
    JQ=./jq python3 sources/run_conformance.py --json              # machine-readable report
    JQ=./jq python3 sources/run_conformance.py --list              # print cases, run nothing
    JQ=./jq python3 sources/run_conformance.py --select 'reduce'   # develop one construct

Environment:
    JQ         command that runs the candidate. Required -- this harness is language-neutral
               and deliberately has no default implementation language.

Exit codes:
    0   every case that ran passed
    1   at least one case failed or errored
    2   the harness could not run: bad usage, missing corpus, or a stale exclusion
"""

from __future__ import annotations

import argparse
import json
import os
import re
import shlex
import subprocess
import sys
from dataclasses import dataclass, field
from pathlib import Path

HERE = Path(__file__).resolve().parent
CORPUS = HERE / "jq.test"
EXCLUSIONS = HERE / "exclusions.txt"

#: A case that has not produced output in this long is not going to. jq's own suite runs the
#: whole corpus in under a second; anything near this bound is a runaway generator.
DEFAULT_TIMEOUT = 10.0

PASS, FAIL, ERROR, SKIP = "pass", "fail", "error", "skip"

#: jq's documented exit codes, which this kit's interface contract adopts. The distinction is
#: load-bearing: the corpus's %%FAIL cases are programs that must not compile, while an ordinary
#: case may legitimately raise at run time part-way through its output and still be correct.
EXIT_COMPILE_ERROR = 3
EXIT_RUNTIME_ERROR = 5


def split_lines(text: str) -> list[str]:
    """Split on newlines only.

    ``str.splitlines`` is Unicode-aware and also breaks on U+000B, U+000C, U+0085, U+2028, and
    U+2029. The corpus contains cases whose expected output embeds those code points inside JSON
    strings -- ``trim, ltrim, rtrim`` over the Unicode whitespace set is one -- and splitting
    there shreds one JSON value into several, failing a correct implementation.
    """
    lines = text.split("\n")
    if lines and lines[-1] == "":
        lines.pop()
    return lines


@dataclass
class Case:
    """One corpus case: a program, an input, and what it must produce.

    ``expect_failure`` cases are the corpus's ``%%FAIL`` blocks. Upstream compares their
    diagnostic text; this runner requires only that the candidate reject the program. The
    expected strings are jq's exact C-implementation diagnostics, down to the caret art
    underlining the offending token -- reproducing them is reverse-engineering an
    implementation, not conforming to a specification. The text is parsed and reported so a
    reader can see what upstream said, and is never compared.
    """

    line: int
    program: str
    stdin: str = ""
    expected: list[str] = field(default_factory=list)
    expect_failure: bool = False
    diagnostic: str = ""


@dataclass
class Result:
    case: Case
    status: str
    detail: str = ""
    actual: list[str] = field(default_factory=list)
    return_code: int | None = None
    stderr: str = ""


class HarnessError(Exception):
    """A fault in the kit or its invocation, never a fault in the candidate."""


# --------------------------------------------------------------------------------------------
# Corpus parsing
# --------------------------------------------------------------------------------------------


def parse_corpus(text: str) -> list[Case]:
    """Parse the jq test corpus.

    The format is documented in the corpus's own header: cases are groups of lines separated by
    blank lines; blank lines and lines starting with ``#`` are ignored. A case is a program
    line, an input line, and then zero or more expected output lines. A case preceded by a
    ``%%FAIL`` or ``%%FAIL IGNORE MSG`` marker is a program line followed by the diagnostic
    upstream jq emits, which may itself span several lines of source excerpt and caret art.
    """
    cases: list[Case] = []
    block: list[tuple[int, str]] = []
    expect_failure = False
    lines = split_lines(text)

    def flush() -> None:
        nonlocal block, expect_failure
        if block:
            cases.append(_case_from_block(block, expect_failure))
        block = []
        expect_failure = False

    for number, raw in enumerate(lines, start=1):
        stripped = raw.strip()
        if not stripped:
            flush()
            continue
        if raw.startswith("%%FAIL"):
            flush()
            expect_failure = True
            continue
        # A '#' comment closes nothing: upstream places section banners between cases, always
        # with blank lines around them, and never inside a case.
        if raw.lstrip().startswith("#") and not block:
            continue
        if raw.lstrip().startswith("#"):
            continue
        block.append((number, raw))
    flush()
    return cases


def _case_from_block(block: list[tuple[int, str]], expect_failure: bool) -> Case:
    line, program = block[0]
    if expect_failure:
        diagnostic = "\n".join(text for _, text in block[1:])
        return Case(line=line, program=program, expect_failure=True, diagnostic=diagnostic)
    if len(block) < 2:
        raise HarnessError(
            f"{CORPUS.name}:{line}: case has a program but no input line; the corpus is malformed"
        )
    return Case(
        line=line,
        program=program,
        stdin=block[1][1],
        expected=[text for _, text in block[2:]],
    )


# --------------------------------------------------------------------------------------------
# Exclusions
# --------------------------------------------------------------------------------------------


def parse_exclusions(path: Path) -> list[str]:
    """Read the declared exclusions: one verbatim program line per entry, ``#`` for reasons."""
    if not path.is_file():
        return []
    return [
        line
        for line in split_lines(path.read_text(encoding="utf-8"))
        if line.strip() and not line.lstrip().startswith("#")
    ]


def apply_exclusions(cases: list[Case], exclusions: list[str]) -> set[int]:
    """Return the corpus line numbers of excluded cases.

    An exclusion that matches nothing is a hard error rather than a shrug. The corpus is pinned
    by hash, so a stale exclusion means the pin moved without the exclusion list being revisited
    -- and a silent no-op there would quietly re-admit a case the kit cannot run.
    """
    by_program: dict[str, list[Case]] = {}
    for case in cases:
        by_program.setdefault(case.program, []).append(case)

    excluded: set[int] = set()
    stale: list[str] = []
    for program in exclusions:
        matched = by_program.get(program)
        if not matched:
            stale.append(program)
            continue
        excluded.update(case.line for case in matched)
    if stale:
        listed = "\n".join(f"    {program}" for program in stale)
        raise HarnessError(
            f"{EXCLUSIONS.name}: these exclusions match no case in {CORPUS.name}:\n{listed}\n"
            "The corpus and the exclusion list have drifted apart."
        )
    return excluded


# --------------------------------------------------------------------------------------------
# Comparison
# --------------------------------------------------------------------------------------------


def jv_equal(left: object, right: object) -> bool:
    """Compare two decoded JSON values the way jq's own ``jv_equal`` does.

    Structural, not textual: ``1`` and ``1.0`` are the same jq value and the corpus relies on
    that. Python's ``==`` almost does this, but it also equates ``True`` with ``1`` and
    ``False`` with ``0``, which jq does not; booleans are therefore matched by identity of type
    before anything else.
    """
    if isinstance(left, bool) or isinstance(right, bool):
        return isinstance(left, bool) and isinstance(right, bool) and left is right
    if isinstance(left, (int, float)) and isinstance(right, (int, float)):
        return left == right
    if isinstance(left, list) and isinstance(right, list):
        return len(left) == len(right) and all(jv_equal(a, b) for a, b in zip(left, right))
    if isinstance(left, dict) and isinstance(right, dict):
        return left.keys() == right.keys() and all(jv_equal(left[k], right[k]) for k in left)
    if type(left) is not type(right):
        return False
    return left == right


def _decode(line: str) -> tuple[bool, object]:
    try:
        return True, json.loads(line)
    except ValueError:
        return False, line


def outputs_match(expected: list[str], actual: list[str]) -> bool:
    if len(expected) != len(actual):
        return False
    for want, got in zip(expected, actual):
        want_ok, want_value = _decode(want)
        got_ok, got_value = _decode(got)
        if want_ok and got_ok:
            if not jv_equal(want_value, got_value):
                return False
        elif want.strip() != got.strip():
            return False
    return True


# --------------------------------------------------------------------------------------------
# Execution
# --------------------------------------------------------------------------------------------


def run_case(case: Case, argv: list[str], timeout: float) -> Result:
    try:
        completed = subprocess.run(
            [*argv, "-c", case.program],
            input=case.stdin,
            capture_output=True,
            text=True,
            timeout=timeout,
        )
    except subprocess.TimeoutExpired:
        return Result(case, ERROR, detail=f"timed out after {timeout:g}s")
    except OSError as exc:
        raise HarnessError(f"cannot execute {shlex.join(argv)}: {exc}") from exc

    actual = split_lines(completed.stdout)
    stderr = completed.stderr.strip()
    code = completed.returncode
    first_diagnostic = split_lines(stderr)[0] if stderr else ""

    if case.expect_failure:
        # The corpus's %%FAIL cases are programs that must be rejected at compile time. Accepting
        # one and then failing at run time is a different, wrong behaviour, so the compile-error
        # code specifically -- not merely a non-zero exit -- is what passes here.
        if code == EXIT_COMPILE_ERROR:
            return Result(case, PASS, return_code=code, stderr=stderr)
        detail = (
            "program was accepted, but the corpus marks it %%FAIL"
            if code == 0
            else f"exited {code}; a rejected program must exit {EXIT_COMPILE_ERROR}"
        )
        return Result(case, FAIL, detail=detail, actual=actual, return_code=code, stderr=stderr)

    if code == EXIT_COMPILE_ERROR:
        return Result(
            case,
            FAIL,
            detail=f"program did not compile: {first_diagnostic}",
            actual=actual,
            return_code=code,
            stderr=stderr,
        )
    if code not in (0, EXIT_RUNTIME_ERROR):
        # A runtime error is legitimate: several cases raise part-way through a generator and are

</pblock>

        # judged on the outputs produced before the raise, exactly as upstream judges them. Any
        # other non-zero status is the program failing in a way the contract does not describe.
        return Result(
            case,
            FAIL,
            detail=f"exited {code}: {first_diagnostic}",
            actual=actual,
            return_code=code,
            stderr=stderr,
        )
    if not outputs_match(case.expected, actual):
        return Result(
            case,
            FAIL,
            detail="output mismatch",
            actual=actual,
            return_code=code,
            stderr=stderr,
        )
    return Result(case, PASS, actual=actual, return_code=code, stderr=stderr)


# --------------------------------------------------------------------------------------------
# Reporting
# --------------------------------------------------------------------------------------------


def _render_failure(result: Result) -> str:
    case = result.case
    lines = [
        f"FAIL {CORPUS.name}:{case.line}  {result.detail}",
        f"    program:  {case.program}",
    ]
    if not case.expect_failure:
        lines.append(f"    input:    {case.stdin}")
        lines.append(f"    expected: {case.expected if case.expected else '(no output)'}")
        lines.append(f"    actual:   {result.actual if result.actual else '(no output)'}")
    if result.stderr:
        lines.append(f"    stderr:   {split_lines(result.stderr)[0]}")
    return "\n".join(lines)


def main(argv: list[str] | None = None) -> int:
    parser = argparse.ArgumentParser(
        description="Run the upstream jq conformance corpus against a candidate implementation.",
    )
    parser.add_argument("--jq", default=None, help="candidate command (default: $JQ)")
    parser.add_argument("--timeout", type=float, default=DEFAULT_TIMEOUT, help="seconds per case")
    parser.add_argument("--json", action="store_true", help="machine-readable report")
    parser.add_argument("-v", "--verbose", action="store_true", help="list passing cases too")
    parser.add_argument("--list", action="store_true", help="print the cases and run nothing")
    parser.add_argument(
        "--select",
        default=None,
        metavar="REGEX",
        help="run only cases whose program matches REGEX (development aid; the acceptance "
        "gate always runs the whole corpus)",
    )
    args = parser.parse_args(argv)

    try:
        return _run(args)
    except HarnessError as exc:
        print(f"error: {exc}", file=sys.stderr)
        return 2


def _run(args: argparse.Namespace) -> int:
    if not CORPUS.is_file():
        raise HarnessError(f"corpus not found at {CORPUS}")

    cases = parse_corpus(CORPUS.read_text(encoding="utf-8"))
    excluded = apply_exclusions(cases, parse_exclusions(EXCLUSIONS))

    selector = re.compile(args.select) if args.select else None
    if selector is not None:
        cases = [case for case in cases if selector.search(case.program)]

    if args.list:
        for case in cases:
            mark = "skip" if case.line in excluded else "run "
            print(f"{mark} {CORPUS.name}:{case.line}  {case.program}")
        print(f"\n{len(cases)} cases, {sum(1 for c in cases if c.line in excluded)} excluded")
        return 0

    command = args.jq or os.environ.get("JQ") or ""
    if not command.strip():
        raise HarnessError(
            "JQ is not set; give the command that runs your implementation, e.g.\n"
            '    JQ="$PWD/jq" python3 sources/run_conformance.py'
        )
    jq_argv = shlex.split(command)

    results: list[Result] = []
    for case in cases:
        if case.line in excluded:
            results.append(Result(case, SKIP, detail="declared in exclusions.txt"))
            continue
        results.append(run_case(case, jq_argv, args.timeout))

    tally = {status: sum(1 for r in results if r.status == status) for status in
             (PASS, FAIL, ERROR, SKIP)}
    summary = (
        f"jq conformance: {tally[PASS]} passed, {tally[FAIL]} failed, "
        f"{tally[ERROR]} errored, {tally[SKIP]} skipped "
        f"(corpus {CORPUS.name} @ jq-1.8.2)"
    )

    if args.json:
        print(json.dumps(
            {
                "candidate": jq_argv,
                "corpus": CORPUS.name,
                "summary": tally,
                "cases": [
                    {
                        "line": r.case.line,
                        "program": r.case.program,
                        "status": r.status,
                        "detail": r.detail,
                        "expect_failure": r.case.expect_failure,
                        "expected": r.case.expected,
                        "actual": r.actual,
                    }
                    for r in results
                    if args.verbose or r.status != PASS
                ],
            },
            indent=2,
        ))
    else:
        for result in results:
            if result.status in (FAIL, ERROR):
                print(_render_failure(result))
            elif args.verbose and result.status == PASS:
                print(f"ok   {CORPUS.name}:{result.case.line}  {result.case.program}")
            elif args.verbose and result.status == SKIP:
                print(f"skip {CORPUS.name}:{result.case.line}  {result.case.program}")
        print(summary)

    return 0 if tally[FAIL] == 0 and tally[ERROR] == 0 else 1


if __name__ == "__main__":
    raise SystemExit(main())

</pblock>

Agent Task

Agent for: blueprint analysis

You are the Team Lead conducting the Product Owner feedback session. You are the team's Agile expert and follow Agile best practices. Your handoff is deliberately completeness-oriented: do not finish until the supplied Commander intent can be handed to Plan as a coherent, buildable epic.

You have received imported source material — one or more documents describing what the product should do. Your job is to analyze that input and produce summary information which will be output to curated files.

The core elements are defined below.

Agile Story Decomposition

Your goal is to do planning for the information you have imported.

You will be creating a set of Agile features and stories. Features group stories; they are the only grouping unit used by ANALYSIS.md and the Commanders Chair. You raise anything the human must decide as either a blocker or a discovery questionnaire. A blocker means the sources cannot be analyzed into a coherent product decomposition. A discovery questionnaire records a finite Commander decision. Mark a questionnaire question "required_before_plan": true when planning cannot author an internally consistent specification until it is answered. Stack selection and unresolved conflicting definitions are required planning decisions.

A story is an atomic testable unit of work that might have acceptance criteria and guardrails at a later stage. Stories include user interface screens, the routes used to service those screens, cli options, api served, batch scripts needed, import/export operations, and other atomic units of work according to agile best practices. Do not create a separate Screens grouping or count; UI screens are stories under the relevant Agile feature.

Story granularity. A story is a normal Agile story: 1 to 5 story points. Never a half point — that is a task, and a task is folded into the story it serves rather than listed beside it. Never twelve — that is split. A story does one thing completely and is releasable on its own; a task is not releasable and is therefore not a story. "Add a button" and "add a test" are tasks. Size by that judgement alone: a story has no token dimension, and story count is an output of correct decomposition, never a target to hit or avoid.

You will note the interrelationships between these elements — for example, a user interface screen uses api calls, and an export depends on the data it reads. Note them to inform how you cut stories; do not build a dependency graph. The graph is constructed later, by plan create.

You will also look at the technologies mentioned in the sources and create a list. If a needed technology is implied but never named — for example a web server is required but none is chosen — surface that as a blocking stack question.

When you look at a story that you have created, if it is complex, attempt to break it up into smaller stories. In the agile process, it is preferable to use multiple smaller stories rather than one larger one.

A very good way to understand this is that the stories you are identifying will eventually, in another command, become markdown files with their specifications included. That markdown will have Acceptance Criteria, GuardRails, and interrelationships. Do not calculate these now; when you define the stories, use the natural boundaries provided within the input files for accuracy of breakdown. Content rearranged at a later step is costly, so cut along the natural groupings that occur within the input.

Derive strategic goals and success criteria only where the sources state or directly imply them. Do not invent business outcomes, thresholds, or acceptance commitments.

Project-fact authority. Prompt context and Commander input are authoritative for the project being analyzed. General knowledge may explain a supplied source, but it must not supply, replace, or refine a project requirement. In particular, do not infer, recall, estimate, or invent a project-specific count, version, limit, threshold, or test total.

Universal acceptance preservation. When a source says all, every, complete, 100%, zero failures, zero errors, or equivalent universal language, preserve that universal form. Do not translate it into a numeric cardinality, a Target: value, an Extract: value, or an exact passed-count assertion. A supplied full test suite proves such a requirement by running unfiltered and succeeding; it does not require the Commander to specify how well the software should work.

Be sure to understand the architecture and component structure.

An input failure that prevents coherent analysis is a blocker. A blocker is not a product choice between identifiable alternatives: emit that choice as a required discovery questionnaire. When you find one or more blockers, write BLOCKERS.md; its mere existence stops downstream steps until the human clears it. When there are no blockers, do not write the file.

Finally - we use our COMPASS to guide the build.

Ownership test for discovery questionnaires. A discovery questionnaire captures a question only the human can answer — a decision the team genuinely cannot make from the sources. Raise one only when the answer turns on something the sources do not contain: business priority, product taste, an external or regulatory constraint, an irreversible trade-off, or a genuinely absent fact (for example, no auth model stated for a product that clearly needs one).

Cross-source conflict test. Compare all source definitions of the same product concept, including default workflows, state vocabularies and transitions, roles and permissions, routes and interfaces, data ownership, and behavioral defaults. Two incompatible definitions with no explicit precedence are a human-owned decision even though both alternatives appear in the sources. Emit one questionnaire question that names the conflicting files and presents the concrete alternatives. Set "required_before_plan": true; do not choose an alternative, merge incompatible definitions, defer the choice to a planning spike, or emit it as BLOCKERS.md when the rest of the product can still be analyzed.

Anything you can derive from the sources, you must derive — into the story list, Surfaced Acceptance Criteria, or SEA_TRIALS. Never ask the human to supply work the team owns. In particular, acceptance criteria, smoke checks, build gates, and test sequences are outputs you synthesize, not questions you ask. Outcome baselines, business thresholds, observation windows, and external measurement sources are different: never invent them. Record the criterion and emit a stable-ID entry under the SEA_TRIALS.md ## Questions section for each missing human-owned measurement fact.

A discovery questionnaire is delivered as a form for the human to answer. Do not raise one for a matter the sources, ANALYZE_COMPASS.md, prior BLOCKERS.md answers, or existing answered questionnaires have already decided, nor for anything you can derive yourself.

Capture the Commander's product and project expectations as concise assertions. Prefer direct, observable wording such as assert the product runs a web server or assert cloud publication is optional. These are stakeholder satisfaction conditions, not implementation tasks.

Inputs

Imported source files — one or more documents from blueprint/sources/, injected below the job block.
Analyze feedback (standing directive) — ANALYZE_COMPASS.md, persistent human direction

injected near the top of this prompt when present. Treat it as authoritative steering for this run; it overrides default decomposition choices where it speaks.

Prior blocker answers — any prior BLOCKERS.md responses, injected if present. Treat settled

items as decided; never re-raise a resolved blocker or duplicate it as a questionnaire.

Existing discovery questionnaires — prior discovery-*.json action items, injected when

present. They are input to this run, not output of it. Every non-empty answer, resolution, and additional_notes field is a Commander decision and is authoritative: apply it to the story list, the stack, the scope, SEA_TRIALS.md, and the quality signal, and never contradict it or re-open it. Do not re-emit an existing questionnaire file, do not ask duplicate or reworded versions of existing unanswered questions, and do not move questionnaire questions into ANALYSIS.md. Questionnaire files are owned by the Commander; Drydock never rewrites them.

COMPASS_EXISTS — true: COMPASS.md exists at the target root. false: write it.
COMPASS_PENDING_FORMAT — true: COMPASS.md was imported as raw Commander intent and is

injected as an input block. Rewrite it into the canonical COMPASS.md format and emit the === BEGIN ARTIFACT COMPASS.md === block. false: if COMPASS_EXISTS: true, omit the block.

DISPLAY_NAME — current display_name value from METADATA.md, or (blank) when not yet set.
SHORT_DESCRIPTION — current short_description value from METADATA.md, or (blank) when not yet set.
Rigging manifest — Rigging/MANIFEST.md, injected below. It names the real selectable

components with their category, purpose, and prerequisites. Use it to recommend a small subset; never open the individual component rule files.

Quality Signal

After analysis, compute one of three quality values:

Quality	Condition	Pipeline
`Blocked`	One or more blockers exist (`BLOCKERS.md` is written)	Halts — `plan create` must not proceed
`Questions`	No blockers; open questions remain	`plan create` may proceed after all required planning questions are answered
`Ready`	No blockers; no open questions	`plan create` may proceed

Blocker — the team cannot produce a coherent analysis or finite decision form. Examples: no understanding of what the product does, unreadable authoritative inputs, or decomposition beyond the story cap. A contradiction with identifiable alternatives is instead a required discovery questionnaire. One or more blockers means you write BLOCKERS.md; its existence is the flag that halts the pipeline. Quality stays Blocked until the human clears it.

Question — an open item that does not stop decomposition. Delivered only as a discovery questionnaire action item and carried forward there. A question marked required_before_plan does not stop analysis, but it gates planning because Plan cannot author a consistent specification without the decision.

Blockers halt analysis progression. Every question marked required_before_plan gates plan create; other questionnaire action items distinguish Questions from Ready but do not gate. TECHNOLOGY_STACK.md never gates planning.

Gap Checklist

Run this checklist over the imported sources (and the ANALYZE_COMPASS.md standing directive, if injected). There are no typed spec files at analyze time — judge each item solely against what the sources state. An item the team cannot proceed without at all is a blocker (see step 3); every other unmet item routes to exactly one of three places — never leave one unrouted, never route it twice:

The team can derive the answer, and it is...	Goes to
scoped to one story	a row in `## Surfaced Acceptance Criteria` (step 6)
project-wide (a guardrail, outcome, or cross-cutting behavior)	a `SEA_TRIALS.md` criterion (step 7)
only the human can decide (the Ownership test, see above)	a discovery questionnaire question (step 9)

Product

[ ] Product goal is stated (what the product is and why)
[ ] Short description is present (one-sentence summary of what the product is)
[ ] Success criteria are stated
[ ] Acceptance criteria are stated per described feature or screen
[ ] Primary workflows are enumerated, not just individual screens or endpoints

Security

[ ] Auth/authz model is named for any protected resource
[ ] Sensitive data handling (PII, secrets, compliance) is addressed where implied

User Experience

[ ] Empty, loading, and error states are described for interactive features
[ ] UI structure is described clearly enough to decompose (web products only)
[ ] A first-time user could complete the primary flow from the sources alone

Architecture

[ ] Stack is named in the sources or prior answers (not empty or TBD)
[ ] Persistence model is described, if the product persists data
[ ] External service calls have defined timeout/failure behavior
[ ] Deployment target is stated

Edge Cases

[ ] Negative paths are addressed (invalid input, auth failure, not-found)
[ ] Concurrency/race conditions are addressed where the sources describe shared state

Core Baseline

Apply only the row matching the project type detected in step 2.

Type	Check
`web`	Primary entry point/landing page is defined; help/support is reachable from navigation
`cli`	Every command/sub-verb has help text defined
`api` / `library`	A reference/discovery entry point is defined
`pipeline` / `event-driven`	Primary trigger and output/consumer are both defined

Tasks

This is a sequential pipeline. Execute the steps in order; each step consumes the prior step's output and emits the named result. Do not re-derive an artifact independently when a prior step already produced its input.

1. Review the sources.

Consumes: imported sources + ANALYZE_COMPASS.md direction + prior BLOCKERS.md answers.
Emits: working notes — what is clear, what is missing, what must be answered.

2. Detect project type.

Consumes: the content and structure of the imported sources.
Emits: one of web | api | cli | library | pipeline | event-driven (or ambiguous).

Detect from what the sources describe, not from any filename — there are no typed spec files at analyze time:

Type	Signals in the sources
`web`	Described screens, pages, or HTTP routes for human users
`api`	Described programmatic endpoints / capabilities; no screens
`cli`	Described commands and sub-verbs; no routes or screens
`library`	Described public API symbols consumed by other code; no routes, no screens
`pipeline`	Described datasets, files, or batch transforms; no routes
`event-driven`	Described topics, queues, or event types

Mixed signals → ambiguous.

3. Identify blockers vs questions.

Consumes: the review notes + completeness checklist.
Emits: the blocker list and the questionnaire action-item list.

First perform the Cross-source conflict test. Blockers halt the pipeline; write BLOCKERS.md only when one or more exist. Questions are carried forward only as discovery questionnaires. A questionnaire records a Commander decision; mark it required_before_plan when a consistent plan depends on the answer. It never resolves a blocker. Do not duplicate a questionnaire question in ANALYSIS.md.

4. Derive the feature and story list.

Consumes: the sources + role notes + project type.
Emits: the Agile feature list and story list at title + high-level AC level (powers ANALYSIS.md ## Story List).
Each feature is an Agile feature area that groups related stories.
Each story corresponds to one spec file scope.
Story cap: ~100 stories. If you identify more than 100, the spec is over-decomposed; surface

this as a blocker and offer to consolidate.

Group all stories under ### Feature: {Feature Name} headings. Do not use Screens as a

separate grouping; screens are stories.

5. Derive test criteria from the story list.

Consumes: the story list (and any explicit acceptance criteria stated in the sources).
Emits: high-level acceptance criteria in ANALYSIS.md Story List rows. Do not emit

SOUNDINGS.md — it is written only by drydock score ac.

6. Derive Surfaced Acceptance Criteria from the Gap Checklist.

Consumes: the Gap Checklist findings routed to "scoped to one story".
Emits: the ## Surfaced Acceptance Criteria rows in ANALYSIS.md (see Output Format), each

tied to a real Story ID from the Story List.

Before finalizing, confirm coverage:
- [ ] Every Gap Checklist item routed as story-scoped has a corresponding row
- [ ] Every row references a real Story ID from the Story List
- [ ] No row restates an AC already explicit in the sources

7. Derive SEA_TRIALS project acceptance.

Consumes: the story list + the Gap Checklist findings routed to "project-wide" + the COMPASS

(existing file or the COMPASS you will emit in step 10).

Emits: structured SEA_TRIALS.md project criteria with stable IDs, one observable behavior or

outcome per criterion, EARS wording and a Pattern where it reads clearly, a guardrail for each prohibition the sources state or imply, and unresolved measurement facts under ## Questions.

Before finalizing, confirm coverage:
- [ ] A guardrail exists for every explicit or clearly implied prohibition
- [ ] A timeout/failure criterion exists for every external service call the sources describe
- [ ] An outcome criterion exists for every stated business/success goal
- [ ] A security/compliance criterion exists where sensitive data or auth is implied
Any statement of complete project behavior, release threshold, end-to-end verification command,

or project-wide deterministic outcome belongs only in SEA_TRIALS.md. Do not emit it as a story-scoped acceptance criterion.

8. Compute the quality signal.

Consumes: the blocker and question counts from step 3.
Emits: Blocked | Questions | Ready per the Quality Signal table. Surfaced Acceptance Criteria

and SEA_TRIALS criteria do not affect this count — only blockers and open questionnaire questions do.

9. Build the discovery questionnaires.

Consumes: the project type + questionnaire action-item list (including Gap Checklist findings

routed to "only the human can decide") + injected Rigging manifest.

Emits: TECHNOLOGY_STACK.md on every run plus one discovery-<slug>.json per open

important question. Set "required_before_plan": true on every unresolved cross-source conflict or other decision without which Plan cannot author one internally consistent specification. These are questionnaire gates and are never emitted in BLOCKERS.md. Gap Checklist questions default to one consolidated discovery-gaps.json; split into discovery-gaps-2.json, etc. only past 5–6 questions in this run. Do not emit a questionnaire for a matter the sources or prior answers have already settled. Do not emit a questionnaire that duplicates an existing unanswered questionnaire. Existing questionnaires are preserved indefinitely and never rewritten or replaced. On re-analysis, emit each genuinely new, non-duplicate question in a new discovery-<slug>.json file.

Story-count sanity question. When the story list exceeds 80 stories, emit one

discovery-story-count.json asking the Commander to confirm the granularity. A high count is a signal that tasks were listed as stories, not a reason to refuse: never drop, merge, or withhold stories to get under the number, and never cap the list. Ask, emit the full list, and let the Commander decide. Phrase the question with the real count and offer a target, for example: "Analysis decomposed this epic into 257 stories, which is high for one Blueprint and usually means tasks were listed as stories. Is this granularity correct, or supply a target NUMBER of stories for a replan." Set "required_before_plan": false — the plan is usable either way. Do not emit it when an equivalent unanswered questionnaire already exists.

10. Emit all output blocks. See Output Format below. Emit the BLOCKERS.md block only when blockers exist; emit the COMPASS.md block when COMPASS_EXISTS: false or COMPASS_PENDING_FORMAT: true.

Output Format

Emit blocks only in this order. Conditional blocks are omitted when their condition is false: ANALYSIS.md, SEA_TRIALS.md, TECHNOLOGY_STACK.md, BLOCKERS.md, COMPASS.md, discovery-identity.json, then discovery-gaps*.json and other discovery-<slug>.json blocks in lexical filename order. Nothing outside the blocks. No preamble, no explanation, no commentary, no tool calls, no <invoke> XML. Start your response with === BEGIN ARTIFACT ANALYSIS.md ===.

=== BEGIN ARTIFACT ANALYSIS.md ===
# Blueprint Analysis: {ProjectName}

## Commander Expectations

- assert {one product or project outcome the Commander expects}

## Crew

| Crew | Charge |
|---|---|
| Commander | Defines intent and decides what done means. |
| Team Lead | Confirms epic completeness and stakeholder expectations. |
| Planning Crew | Authors atomic specifications and the ordered Manifest. |
| Shipyard Crew | Builds the tickets without synchronous Commander access. |

## Story List

Use this exact repeated shape. The `features` summary count must equal the number of
`### Feature:` headings. The `stories` summary count must equal the total number of story rows
across all feature tables.

### Feature: {Feature Name}

| ID | Story | High-level AC |
|---|---|---|
| {FEATURE-SLUG}-001 | {Story title} | {High-level acceptance signal} |

## Surfaced Acceptance Criteria

The analyze step has surfaced these acceptance criteria for `drydock plan` to fold into the
relevant story's typed specification. "None." if the Gap Checklist surfaced no story-scoped items.

| ID | Story ID | Criterion |
|---|---|---|
| AC-001 | {FEATURE-SLUG}-001 | {One observable behavior the story must satisfy} |

## Relationship Model

Infer cross-file delivery relationships from the imported source material. Supporting implementation,
helper, fixture, and test files are evidence for the capability they enable, not independent
stories. Use concise cited paths such as `sources/tests/test_parser.py`.

| Source or group | Relationship type | Related source or group | Evidence | Delivery implication |
|---|---|---|---|---|
| {source path/group} | {instruction-to-test | test-kit-to-implementation | implementation-to-helper | reference-to-replacement | parser-to-normalizer | dependency} | {source path/group} | {specific cited evidence} | {planning consequence} |

## Source Roles

Classify every imported file cited above. `author intent` is routed to COMPASS and is not a
standalone build-context file. Test suites and harnesses are context/staged assets, never
implements files.

| Path | Role | Plan disposition | Build disposition |
|---|---|---|---|
| {sources/path} | {author intent | normative specification and conformance test suite | conformance harness | test helper | reference implementation | source reference | asset} | {compass | context | exclude} | {stage | prompt-only | none} |

Build disposition governs what exists on disk when the build agent runs and when acceptance
executes:

- `stage` places the file in the build directory at `sources/{path relative to sources/}`. Every
  assertion, `ac` check, and Sea Trial `Command:` references it by that build-relative path.
  A test suite or harness the project must execute is always `stage` — a file present only in the
  prompt can be read but not run. **Everything a staged file needs at run time is also `stage`**:
  a harness's imported modules, its normalizer, and its fixtures. Read each staged file's imports
  and open() calls and stage what they name; a harness missing one dependency cannot run at all.
- `prompt-only` supplies the file as prompt context and places nothing on disk.
- `none` neither stages nor supplies it.

Markdown is never staged; use `prompt-only` for it.

## Planning Instructions

### Delivery Shape

State the inferred system/pipeline, major inputs and outputs, and required execution flow.

### Story Realization Map

For every Story ID, state the durable Blueprint scope(s), cited `sources/...` evidence, related
files, and whether it requires a capability, integration, migration, test harness, or acceptance
contract.

### Test and Acceptance Strategy

State focused story tests separately from final Sea Trial verification. Programmatic acceptance is
finite and story-scoped by default.

When the imported sources include a conformance harness and its test suite, exactly one terminal
verification story gates on the complete suite. That story depends on every implementation story,
and its acceptance assertion declares `Suite: full` in its heading block so the full run is
deliberate. Every other story stays bounded and must never run the whole suite: a story that
executes the runner only to prove it works bounds the run with the runner's `--pattern`/`--number`
selector; a feature story runs the slice it owns and declares `Suite: scoped`. A sample proves a
unit works, never that the project is correct.

State a source-supplied numeric release threshold as a Sea Trial, not as a story assertion. A
complete-suite requirement is a proof gate, not a measured release threshold.

### Sequencing and Dependencies

State Manifest ordering constraints, including build-before-test, parser-before-normalizer,
fixture-before-verification, and external dependencies.

### Source Conflicts and Gaps

State contradictions or missing information that must remain blockers or questionnaires. Do not
silently resolve them.

## Analysis Notes

generated: {ISO date}
blueprint: {BLUEPRINT_PATH from job block}

Quality: {Ready | Questions | Blocked}
  blockers: {N}
  questions: {N}
  features: {N}
  stories: {N}
  stack: {declared stack value or "not declared"}
  display_name: {proposed display name derived from the sources, or "not proposed" when DISPLAY_NAME is already set}
  short_description: {one-sentence product description derived from the sources, or "not proposed" when SHORT_DESCRIPTION is already set}

{Non-conformant headers, ambiguous signals, observations. "None." if clean.
Do not add an ## Overview section or any other sections not listed here. Drydock deterministically
adds Source Inventory and Resolved Blockers after this output; do not emit either section.}
=== END ARTIFACT ===

=== BEGIN ARTIFACT SEA_TRIALS.md ===
# Sea Trials: {ProjectName}

Project-level acceptance derived from COMPASS and sources. Emit 3–7 criteria normally, plus any
guardrail the sources state or clearly imply. Emit criteria only — Drydock injects the reader
documentation. Never emit `###` headings or explanatory prose.

## st-001: {Short criterion title}

Type: {technical | behavioral | qualitative | outcome | guardrail}
Required: {yes | no}
Criterion: {One observable behavior or outcome. Preferably EARS-shaped for technical, behavioral, and guardrail; plain English where that reads more clearly, and always for qualitative and outcome.}
Verification: {proof | measurement | evidence | llm}
Pattern: {optional — ubiquitous | event | state | option | unwanted; declare it only when the Criterion is written in that shape}

Emit only populated optional fields. Each field occupies its own line; align values after the
field names. Do not combine fields on one line.
Command: {JSON argv array}
Extract: {regex whose first capture group is the measured number in the command's stdout}
Evidence: {target-relative evidence file}
Baseline: {numeric value}
Operator: {< | <= | == | >= | >}
Target: {numeric value}
Unit: {unit}

A `measurement` criterion carries `Command:` plus either `Extract:` or `Evidence:`. Without them it
is INCONCLUSIVE and can never settle.

`Command:` is a literal argv that runs from the build directory. It never contains a `<placeholder>`
— Drydock does not resolve one, and a placeholder argv silently never runs. Name the staged harness
by its build path (`sources/{name}`) and the deliverable by its real entry point.

`Extract:` lets Drydock read the value from a harness that reports in human-readable text; without
it the command must print `{"value": <number>, "unit": "<unit>"}`. Prefer `Extract:` over asking the
project to emit JSON — a wrapper that computes its own score can report anything.

When the sources supply a conformance harness and require complete conformance, emit exactly one
`proof` criterion that executes the unfiltered full suite. Its criterion says that every supplied
case passes; its `Command:` is the literal full-suite argv. Do not add `Extract:`, `Baseline:`,
`Operator:`, `Target:`, or `Unit:`. The terminal Blueprint assertion declares `Suite: full` and
proves the same Sea Trial with the harness exit status and zero failures/errors where reported.

Use `measurement` only when the source or Commander states a genuinely numeric requirement, such
as latency, throughput, cost, capacity, or an explicit numeric release threshold. Do not ask a
question for a missing threshold when the source already requires all supplied tests to pass.

{Repeat one section per criterion.}

## Questions

### Q-st-001-baseline: {Short question name}

- Origin: analyze-questionnaire
- Status: open

#### Question

{Human-owned missing measurement fact.}

#### Answer
=== END ARTIFACT ===

BLOCKERS.md block (conditional): Emit only when one or more blockers exist. When there are no blockers, do not emit this block — its absence is what lets the pipeline proceed. Never emit the block with placeholder text (e.g. "none", "(omitted)") in place of real blockers; omit it entirely.

=== BEGIN ARTIFACT BLOCKERS.md ===
# Blockers: {ProjectName}

Each blocker is a question the human must answer before `plan create` runs. The Commander records
the decision only under `### Commander Resolution`; the next `drydock analyze` run reads it. Do
not remove the blocker heading or write an answer outside that subsection.

## blocker-001: {Short title}
{What is blocking and why the team cannot proceed without it.}

### Commander Resolution

<!-- Enter the decision that resolves this blocker, then re-run Analyze. -->
=== END ARTIFACT ===

COMPASS.md block (conditional): Emit when COMPASS_EXISTS: false or COMPASS_PENDING_FORMAT: true in the job block. If COMPASS_EXISTS: true and COMPASS_PENDING_FORMAT: false, omit this block entirely.

When COMPASS_PENDING_FORMAT: true, preserve the imported Commander intent, constraints, and guardrails, but normalize them into the canonical sections below. Do not weaken, replace, or summarize away specific strategic direction.

The COMPASS.md is injected into every build step as orientation for the building agent. It must be short (30–40 lines maximum), synthesized, and written for an agent about to write code — not for a human reader, and not as project documentation. Do not reproduce source files verbatim. Do not write API references, usage guides, feature lists, or architecture narrations. Extract only: what the product is and who it serves (one paragraph); hard technical/regulatory/operating constraints (bullets); behavioral guardrails the build agent must never violate (bullets).

=== BEGIN ARTIFACT COMPASS.md ===
# COMPASS: {ProjectName}

## Compass
{One paragraph: what this product is, who it serves, and why it exists.
Written for a developer joining the project for the first time. Be specific and concise.
Do NOT reproduce source file content. Synthesize.}

## Constraints
{Bullet list: hard technical, regulatory, scale, and operating constraints derived from the sources.
These bound what the agent may build — runtime, compatibility, environment, operating limits.
Do NOT list the technology stack here; technologies belong only in TECHNOLOGY_STACK.md.
"- None stated." if the sources are silent.}

## Guardrails
{Bullet list: behavioral rules the building agent must never violate — security, compliance, scale,
performance, irreversible trade-offs, or explicit prohibitions from the Commander.
"- None stated." if the sources are silent.}
=== END ARTIFACT ===

Discovery questionnaires (discovery-*.json) — emit one per open question, none for decided matters. Every block must pass the Ownership test: a decision only the human can make. Use these topics as a checklist of what to probe, but emit a block only where the sources (and any prior answers) leave a human-owned decision open:

identity — the project display name and short description (see the identity rule below)
intent — what the product is, who it serves, how success is measured (only where the sources

genuinely leave the product's purpose or audience open)

stack — the technology stack (see the stack rule below)
guardrails — security, compliance, scale, or performance constraints the sources do not state

but the human must set

gaps — Gap Checklist findings routed to "only the human can decide"; consolidate into one

discovery-gaps.json by default, splitting only past 5–6 questions in a run (step 9)

plus any genuine project-specific decision only the human owns

Underspecified acceptance criteria, success evidence, smoke checks, build gates, and test sequences that the team can derive are outputs you synthesize (into Surfaced Acceptance Criteria or SEA_TRIALS), never questions you ask. Only a Gap Checklist finding that fails the Ownership test becomes a discovery-gaps.json question.

Each questionnaire uses this shape:

=== BEGIN ARTIFACT discovery-{slug}.json ===
{
  "id": "discovery-{slug}",
  "title": "Discovery: {Short Title}",
  "purpose": "{One sentence: what decision this questionnaire resolves.}",
  "questions": [
    {
      "id": "{question_slug}",
      "label": "{Short Label}",
      "prompt": "{Full question for the Product Owner.}",
      "input": "text | textarea | select | checkbox_grid",
      "proposed": "{Optional proposed value for the Commander to confirm or override}",
      "required_before_plan": false,
      "answer": "{Optional current answer. Use the proposed value for generated identity answers; use an empty string for undecided stack selections.}"
    }
  ]
}
=== END ARTIFACT ===

Identity questionnaire rule. When DISPLAY_NAME is (blank) or SHORT_DESCRIPTION is (blank) in the job block, derive a proposed display name and one-sentence short description from the sources, include them in the display_name and short_description summary fields in ANALYSIS.md, and emit a discovery-identity.json questionnaire for the Commander to confirm or override. Use the proposed field and the answer field on each question to pre-fill the proposed value. The answer field must match the value analyze writes to METADATA.md so QuarterDeck does not render an empty box. Do not emit discovery-identity.json when both DISPLAY_NAME and SHORT_DESCRIPTION are already set (i.e., neither is (blank)).

=== BEGIN ARTIFACT discovery-identity.json ===
{
  "id": "discovery-identity",
  "title": "Discovery: Project Identity",
  "purpose": "Confirm the proposed display name and short description before planning.",
  "questions": [
    {
      "id": "display_name",
      "label": "Display Name",
      "prompt": "The display name Drydock will use for this project. Edit to override the proposal.",
      "input": "text",
      "proposed": "{Proposed display name derived from the sources}",
      "answer": "{Proposed display name derived from the sources}"
    },
    {
      "id": "short_description",
      "label": "Short Description",
      "prompt": "One-sentence description of what this project does. Edit to override the proposal.",
      "input": "textarea",
      "proposed": "{Proposed one-sentence description derived from the sources}",
      "answer": "{Proposed one-sentence description derived from the sources}"
    }
  ]
}
=== END ARTIFACT ===

Technology Stack rule. Always emit TECHNOLOGY_STACK.md: one row per technology the sources show the product using, in dependency order (language, framework, persistence, infrastructure, tooling). Drydock discards the block when the file already exists, so this proposal never overwrites a Commander decision.

The Rigging column names a file from the injected Rigging catalog, or — when no catalog file governs that technology. A technology with no Rigging file is normal and expected — record the technology anyway. Never omit a technology because the catalog lacks a matching file, never invent a Rigging filename that is not in the catalog, and never list a Rigging file that no row uses.

Derive the technologies from the sources. Where the sources are silent on a slot the product plainly needs, propose the conventional choice and say so in Notes. Do not emit a stack blocker and do not raise a stack questionnaire; the Commander edits this file directly.

=== BEGIN ARTIFACT TECHNOLOGY_STACK.md ===
# Technology Stack

| Technology | Rigging | Notes |
|---|---|---|
| {Technology name as the product uses it} | {catalog filename or —} | {Short note, or empty} |
=== END ARTIFACT ===

Story Guidance rule. Emit STORY_GUIDANCE.json only when the imported material states its own build breakdown — a conformance corpus grouped by chapter, a suite partitioned by feature, a specification whose sections name the units of work. Where the sources state no breakdown, omit the block entirely; inventing one adds nothing the Story List does not already carry.

One entry per story the breakdown names, in build order. id is the story id you used in the Story List. gate is optional and is the argv Drydock runs to decide that story — supply it only when the sources stage a runner that accepts a scope selector, and scope it to the cases that story implements. note says which part of the source material the entry came from.

Do not write a provenance field. Drydock assigns it. Every entry you emit is recorded as derived, never as Commander guidance: a gate written by the same model that plans the work is a criterion, not an oracle, and labelling it otherwise would make the plan its own examiner. Guidance the Commander supplied is already present in the injected inputs and is preserved whatever you emit — never restate, rename, or re-scope one of those ids.

=== BEGIN ARTIFACT STORY_GUIDANCE.json ===
{
  "stories": [
    {
      "id": "{story id from the Story List}",
      "gate": ["{runner}", "{scope selector for this story's cases}"],
      "note": "{the source section this breakdown came from}"
    }
  ]
}
=== END ARTIFACT ===

Hard Rules

Emit only === BEGIN ARTIFACT <name> === / === END ARTIFACT === blocks. The name is typed once, at the open. The closing delimiter is the constant token === END ARTIFACT === — never repeat the name in it, and never substitute the artifact's title or heading for it. No text outside them — no preamble, no summary, no prose, no commentary, no tool calls, no <invoke> or <function_calls> XML. Any output outside a delimited block is a protocol violation and will cause the run to fail.
Emit the BLOCKERS.md block only when one or more blockers exist; its existence halts the pipeline.
Emit the COMPASS.md block only when COMPASS_EXISTS: false or

COMPASS_PENDING_FORMAT: true.

Emit discovery-identity.json only when DISPLAY_NAME or SHORT_DESCRIPTION is (blank) in the job block. When both are already set, omit it entirely.
COMPASS.md must be ≤40 lines. It is injected into every build step — brevity is a hard requirement.
COMPASS.md is orientation for a build agent, not project documentation. Never reproduce source

file content verbatim, never write API references or usage guides, never narrate architecture. Synthesize intent, constraints, and guardrails only.

Never enumerate the technology stack in COMPASS.md. The stack is recorded once, in

TECHNOLOGY_STACK.md, and reaches the builder through per-story stack: fields.

Never emit a questionnaire that asks the Commander to select the technology stack or Rigging

files. That decision lives in TECHNOLOGY_STACK.md.

Do not include ## Questions or any duplicate question list in ANALYSIS.md. Nonblocking

questions live only in discovery-*.json questionnaire action items.

## Surfaced Acceptance Criteria is always present in ANALYSIS.md, "None." when empty. Its row

count is never counted toward the Quality Signal or the questions/blockers summary fields.

Every Gap Checklist finding routes to exactly one of: ## Surfaced Acceptance Criteria,

SEA_TRIALS.md, or a discovery-gaps.json question — never more than one, never left unrouted.

Gap Checklist questions default to one discovery-gaps.json; split into numbered continuations

only past 5–6 questions in a single run.

Emit a discovery-*.json questionnaire only for a decision only the human can make (the

Ownership test). Never emit one for a matter the sources or prior answers have already decided, never as a generic catch-all, and never for work the team can derive itself (acceptance criteria, success evidence, smoke checks, build gates, test sequences — these are synthesized outputs).

Compare competing definitions of every shared product concept across all imported sources. Emit

each unresolved incompatibility as a questionnaire question with "required_before_plan": true; never silently select, merge, or defer conflicting defaults.

Story list is titles + high-level AC only. Do not write typed spec file content.
Story list uses ### Feature: {Feature Name} headings and | ID | Story | High-level AC |

tables only. Do not emit | # | Story |, unheaded story tables, a separate Screens section, or narrative notes inside ## Story List.

The features summary count equals the number of ### Feature: headings. The stories

summary count equals the number of story rows in those feature tables. These counts must tie to the Analysis tab and Commanders Chair.

Story cap: if you derive more than 100 stories, surface as a blocker.
Never re-ask a question already settled by ANALYZE_COMPASS.md, a prior BLOCKERS.md, or an

existing questionnaire answer. Never emit a duplicate or reworded version of an existing unanswered questionnaire.

Preserve every existing questionnaire indefinitely. Never rewrite or replace an existing

questionnaire; emit genuinely new, non-duplicate questions in new discovery-<slug>.json files.

Never open individual Rigging component rule files; the catalog supplies filenames only.
Never emit a select or multiselect question without a non-empty options list. A free-text

decision uses "input": "textarea".

A named technology with a matching manifest component informs the proposal; it is not a confirmed

selection. A named technology with no matching component is a discovery questionnaire.

Story List high-level AC: use acceptance criteria stated in the sources where present; otherwise

synthesize one milestone per feature area / screen / persistence area.

SEA_TRIALS.md criteria are project-level and use stable st-* IDs. Preserve prior IDs for the

same criterion on reruns. Technical and behavioral criteria normally use Blueprint proof; outcomes use measurement; subjective criteria use evidence-bound LLM judgment.

Technical, behavioral, and guardrail criteria are preferably written in EARS, declaring the

Pattern their Criterion matches:

Pattern	Shape
`ubiquitous`	`The <system> shall <response>`
`event`	`When <trigger>, the <system> shall <response>`
`state`	`While <state>, the <system> shall <response>`
`option`	`Where <feature>, the <system> shall <response>`
`unwanted`	`If <trigger>, then the <system> shall <mitigation>`

A criterion in EARS begins with its pattern's leading keyword (The, When, While, Where, If) and makes the system under test the grammatical subject of shall. Prefer the system's point of view — The parser shall pass every supplied CommonMark conformance example. over Every supplied CommonMark conformance example shall pass. Where a requirement is clearer in plain English, write it in plain English and omit Pattern; clarity outranks the notation. Pattern is optional on every criterion, and declaring it commits the sentence to that shape.

Never emit a Notation field. Drydock derives it from the Pattern and the Criterion, marking

each criterion ears or other. Both are equally binding and neither affects any verdict.

Qualitative and outcome criteria are plain English and leave Pattern blank. They are measurement

contracts settled by Baseline, Operator, Target, and Unit.

A guardrail is an absolute prohibition the project may never do — a never, not a target. It

is a prohibition written either as Pattern: unwanted when it has a trigger (If <trigger>, then the <system> shall <mitigation>), or as a negative Pattern: ubiquitous when the prohibition is unconditional (The <system> shall not/never <action>). A breach fails delivery regardless of every score. Raise one only where the sources state or clearly imply a prohibition; never invent one to be thorough.

Prefer proof or measurement for required technical, behavioral, and guardrail criteria. A

required assertion resting only on llm judgment reduces the project's acceptance coverage score.

Never invent outcome baselines, targets, units, or external measurement sources. Emit stable-ID

## Questions records for missing human-owned facts. Emit - None. when none remain.

Never emit a discovery-sea-trials.json block. Sea Trials questions live in the SEA_TRIALS.md

## Questions section; Drydock projects them into that questionnaire itself.

The SEA_TRIALS.md ## Questions section holds only human-owned measurement facts (baselines,

targets, workloads, business measures). Never place a stack or Rigging selection question there — the technology stack is owned solely by TECHNOLOGY_STACK.md and must appear in no questionnaire. Drydock drops any stack/Rigging question found in the Sea Trials Questions section.

All questionnaire JSON must be valid JSON.
Do not write to blueprint/ or read MANIFEST.md. Read imported sources — there are no

typed spec files at analyze time, so do not inspect or invent them.

Do not fabricate requirements or problems the sources do not imply. A genuinely absent decision

(e.g. no auth model stated) is a real gap — route it under this prompt's blocker and questionnaire rules, not as an invented requirement.

Use the preceding job metadata, prior answers (if any), and imported source files for this run.