Lemon

The Lemon program is an LALR(1) parser generator. It takes a context free grammar and converts it into a subroutine that will parse a file using that grammar. Lemon is similar to the much more famous programs "YACC" and "BISON". But lemon is not compatible with either yacc or bison. There are several important differences: Lemon uses a different grammar syntax which is less prone to programming errors. The parser generated by Lemon is both re-entrant and thread-safe. Lemon includes the concept of a non-terminal destructor, which makes it much easier to write a parser that does not leak memory.