SLY - Sly Lex Yacc

SLY is a 100% Python implementation of the lex and yacc tools, loosely based on the traditional compiler construction tools lex and yacc, implementing the LALR(1) parsing algorithm. It provides a bare-bones, yet fully capable, library for writing parsers in Python. The current version is 0.5. As of December 21, 2025, the project has been officially retired by its author, and no further maintenance is expected.