Language definition files

Lark is a Python parsing toolkit used to define grammars and convert raw text into annotated parse trees. It serves as an abstract syntax tree generator and a grammar definition language for specifying language rules through terminals and regular expressions. The library provides two primary parsing implementations: an Earley parsing library capable of handling all context-free languages, including those with ambiguity and left-recursion, and a high-performance LALR parsing library designed for deterministic languages with low memory overhead. Beyond core parsing, the toolkit includes capabi

nom is a Rust parser combinator framework used to build complex parsers for binary and text data. It functions as an abstract syntax tree generator and a bit-level binary parser, allowing users to construct structured data by combining small, reusable parsing functions. The framework provides specialized support for zero-copy binary parsing, extracting data as slices from raw byte arrays to avoid memory allocations. It also includes a streaming data parser capable of processing partial input chunks from networks or files and signaling when additional input is required. The project covers a b

ANTLR is a grammar-based code generator and multi-language parser generator used to design and implement custom languages. It functions as a toolkit for transforming formal language definitions into executable source code for processing structured text or binary files, while providing a framework for automatically constructing and traversing hierarchical parse trees. The project is distinguished by its ability to generate lexers and parsers in various target programming languages from a single shared grammar definition. It supports grammars containing direct left recursion and utilizes adapti

ast-grep is a command-line utility and static analysis engine designed for searching, linting, and refactoring source code. It operates by identifying and transforming code blocks based on their underlying syntactic structure rather than relying on text-based or regular expression matching. The tool utilizes a language-agnostic abstraction to normalize diverse programming grammars into a unified tree structure. By employing a rule-driven engine, it allows users to define complex patterns that capture syntax nodes as variables, enabling consistent and syntactically valid modifications across e

Tree-sitter is a parsing system and incremental parsing framework designed to generate high-performance syntax trees from source code. It functions as a language parsing engine that compiles formal grammar definitions into portable code, which can then be integrated into text editors and development tools to facilitate structural analysis, code navigation, and syntax highlighting. The project distinguishes itself through its ability to maintain valid, usable syntax tree structures even when source code contains syntax errors or incomplete fragments. It utilizes a generalized parsing algorithm

Chumsky is a parser combinator library used to build high-performance parsers by composing small parsing functions into complex grammars. It provides multiple parsing engines, including recursive descent and precedence-climbing implementations for resolving the order of operations in mathematical and logical expressions. The library is distinguished by its zero-copy text parsing, which minimizes memory allocations to increase throughput, and its ability to run without a standard library for use in embedded or resource-constrained environments. It also features an error-recovering parser that

Participle is a Go parser generator and toolkit for building language frontends. It provides a declarative grammar framework that uses reflection and struct tags to map input patterns directly into typed data structures. The library features a stateful lexical analyzer that employs state machines to handle nested or modal patterns. It includes a lexer code generator to produce optimized code, reducing runtime memory allocations and increasing throughput. The project covers recursive descent parsing with support for union types via sealed interfaces and custom parsing logic through interface-

JavaParser is a library that parses Java source code up to version 12 into an Abstract Syntax Tree (AST), enabling programmatic analysis, transformation, and generation of Java code. It serves as a parser, code analyzer, code generator, comment parser, and symbol resolver, providing a unified toolkit for working with Java source at the AST level. The library distinguishes itself through several integrated capabilities that go beyond basic parsing. It includes a symbol resolution engine that resolves type and symbol references across files for accurate semantic analysis, and an error-recovery

Semantic is a Haskell-based library and command-line tool designed for polyglot source code analysis. It functions as a static program analysis framework and a polyglot abstract syntax tree parser that converts multiple programming languages into structured syntax trees based on grammar definitions. The system distinguishes itself through a semantic code comparison engine that detects structural and meaningful changes between code versions rather than relying on textual differences. It further enables analysis across different programming syntaxes by translating surface languages into a unifi

Tree-sitter-markdown is a parsing library that analyzes plain text Markdown documents to generate a concrete syntax tree for editors and syntax highlighters. It functions as a code editor parsing grammar and a markdown syntax tree generator, converting markup text into structured nodes representing headings, lists, links, and text formatting. The library uses an incremental LR parsing engine to process source text and maintain the syntax tree efficiently during edits. It relies on context-aware lexing to switch tokenization rules dynamically based on the current parser state, alongside compi

Parser is a Ruby source code parser that converts raw source text into structured abstract syntax trees for static analysis and code manipulation. It features dynamic dispatch mechanisms that select specific grammar and tokeniser implementations at runtime, supporting both the executing interpreter version and explicitly targeted language specification versions. The library constructs abstract syntax tree nodes as frozen, immutable objects while tracking exact source file coordinates and character ranges for each node. Developers can supply custom builder objects to control how tree nodes ar