skvadrik/re2c

Health v2 · maintenance only

Flags: no_license

Adoption not part of the score

1308 stars · 201 forks observed · 2026-08-28

What it is AI-extracted, prompt v1, taxonomy v1, 2026-08-30, confidence not recorded

re2c is a free and open-source lexer generator that compiles regular expressions into fast, direct-coded lexers for many languages including C/C++, Go, Rust, Python, and Java. It embeds generated finite state automata directly as conditional jumps and comparisons, producing code that is as fast as hand-written lexers and easier to debug than table-driven alternatives.

Use cases

• generate a fast tokenizer for a C or C++ compiler
• generate lexer code in Go or Rust from regular expressions
• replace a slow table-driven lexer with direct-coded automata
• build a custom DSL parser with submatch extraction
• embed a lexer inside existing source code without a fixed program template
• generate Unicode-aware lexers with UTF-8/UTF-16/UTF-32 support

When to choose

• you need maximum lexer performance comparable to hand-coded tokenizers
• you want generated lexer code that is readable and debuggable
• you need lexers in one of many supported target languages
• you need flexible integration of lexing into arbitrary code rather than a fixed template
• you need submatch extraction with minimal overhead

When to avoid

• you want a full parser generator (use yacc/bison/ANTLR alongside)
• you prefer table-driven lexer generation like flex
• you need a runtime regex engine rather than compile-time code generation
• your target language is not supported and you cannot write a syntax file

Facets

cli-tool · maturity stable

parser compiler developer-tools parsers programming-languages developer-tools compilers windows cross-platform cli lexer-generator regular-expressions code-generation dfa tokenizer multi-language linux macos

Member repositories

For agents

markdown · JSON · MCP: product_card(name="skvadrik/re2c")