A modern parsing library for Python


Lark can parse any context-free grammar.

Lark provides:

  • Advanced grammar language, based on EBNF
  • Three parsing algorithms to choose from: Earley, LALR(1) and CYK
  • Automatic tree construction, inferred from your grammar
  • Fast unicode lexer with regexp support, and automatic line-counting

Lark's code is hosted on Github:


$ pip install lark-parser

Syntax Highlighting

Documentation Index