Simon Willison’s Weblog

Simple Top-Down Parsing in Python. Eye-opening tutorial on building a recursive descent parser for Python, in Python that uses top-down operator precedence.

Posted 19th July 2008 at 11:37 pm

Recent articles

Embracing the parallel coding agent lifestyle - 5th October 2025
Designing agentic loops - 30th September 2025
Claude Sonnet 4.5 is probably the "best coding model in the world" (at least for now) - 29th September 2025

compilers 16 effbot 4 fredrik-lundh 7 parsing 12 python 1190 recursivedescent 1

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