Lemon Parser Generator

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Lemon Parser Generator
Developer(s) D. Richard Hipp
Written in C
Operating system Cross-platform
Type Parser generator
License Public domain
Website www.hwaci.com/sw/lemon/

Lemon is a parser generator, maintained as part of the SQLite project, that generates an LALR parser in the C programming language from an input context-free grammar. The generator is quite simple, implemented in a single C source file with another file used as a template for output. Lexical analysis is performed externally.

Lemon is similar to bison and yacc; however it is not compatible with these programs. The grammar input format is different, so as to help prevent common coding errors. Other distinctive features include a reentrant, thread-safe output parser, and the concept of "non-terminal destructors" that try to make it easier to avoid leaking memory.

SQLite uses Lemon with a hand-coded tokenizer to parse SQL strings.

In 2008 a Lemon-generated parser was suggested to replace the bison-generated parser used for the PHP programming language; as of 2010 this project was listed as "in the works".[1]


  1. ^ Kneuss, Etienne (2008-03-25). "Request for Comments: Replace Bison based parser with Lemon". PHP Wiki. Retrieved 2010-05-08. 


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