# ANTLR v4

ANTLR (ANother Tool for Language Recognition) is a powerful parser generator for reading, processing, executing, or translating structured text or binary files.

Repository: https://github.com/antlr/antlr4
Canonical: https://ross.abutalabs.com/products/antlr-v4
Homepage: http://antlr.org
Language: Java
License: BSD-3-Clause
License Family: permissive
Topics: parsing, parser-generator, antlr, antlr4, java, grammar, python, parse, language-recognition, javascript, csharp, swift, cpp, golang, php, dart
Last push: 2026-02-16T21:29:09+00:00
Link (homepage): http://antlr.org

## Health v2 (maintenance only)
Score: 53/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 67, release rhythm 8, longevity 100
- inputs: {"age_days": 6055, "days_push": 198, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 18986, forks 3462 (observed 2026-08-28T04:11:27.326516+00:00)

## What it is
ANTLR v4 is a parser generator that reads grammar files and produces parsers, lexers, and parse-tree walkers in ten target languages including Java, Python, C++, and Go. It is widely used to build languages, interpreters, translators, and tools that process structured text or binary formats.

## Use cases
- build a programming language or DSL
- parse structured text files with a custom grammar
- generate a parser in multiple languages from one grammar
- write a SQL or config file parser
- translate or transpile source code
- build an interpreter for a scripting language

## When to choose
- you need a battle-tested parser generator with grammars for many real-world languages
- you want generated parsers in several target languages from a single grammar
- you need parse trees with listener/visitor APIs for semantic actions

## When to avoid
- you only need simple regex-based text matching
- you want a hand-written recursive descent parser with full control
- your project requires strict semver dependency guarantees

## Facets
- artifact type: library
- maturity: stable
- function: parser, compiler, interpreter, developer-tools
- domain: parsers, programming-languages, compilers, developer-tools
- platform: jvm, python, cpp, dotnet, go, cross-platform, php
- tags: parser-generator, grammar, antlr4, parse-trees, ll-parsing, code-generation, dsl, javascript, swift

## Member repositories
- antlr/antlr4 (main) score 53
- antlr/grammars-v4 (examples) score 76

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:11:27.326516+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-29T17:00:42.687650+00:00, confidence not recorded.
  - readme: https://github.com/antlr/antlr4 (fetched 2026-08-28T04:11:27.326516+00:00, sha ff2e3bbfc226)
  - homepage: http://antlr.org (fetched 2026-08-29T07:59:02.554515+00:00, sha 979d95576f4b)
- Data as of 2026-08-30T08:39:29.467469+00:00.