---
id: ply
version: "3.11"
license: BSD
license_treatment: permissive
maintenance: abandoned
---

# ply — Python Lex & Yacc

License: permissive · Maintenance: abandoned · Popularity: top 1,000 on PyPI

## Install

pip install ply
uv add ply
poetry add ply

## Description

PLY is yet another implementation of lex and yacc for Python. Some notable
features include the fact that its implemented entirely in Python and it
uses LALR(1) parsing which is efficient and well suited for larger grammars.

PLY provides most of the standard lex/yacc features including support for empty 
productions, precedence rules, error recovery, and support for ambiguous grammars. 

PLY is extremely easy to use and provides very extensive error checking. 
It is compatible with both Python 2 and Python 3.

## AI interpretation — verify before relying

PLY is a Python implementation of lex and yacc that provides lexical analysis and LALR(1) parsing for building compilers and interpreters. It handles grammar definition, tokenization, and syntax analysis with built-in error recovery and ambiguity support.

Verdict: PLY remains a solid, dependency-free choice for building parsers and lexers, with a permissive BSD license and top_1000 popularity. Its abandonment since 2018-02-15 is a significant concern: no security updates, no bug fixes, and no maintenance. Use only if you can maintain a fork or if your grammar requirements are simple and stable.

[View on SkillFed](https://skillfed.io/packages/ply) · [View on PyPI](https://pypi.org/project/ply/)