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

Large Language Models can run tools in your terminal with LLM 0.26 - 27th May 2025
Highlights from the Claude 4 system prompt - 25th May 2025
Live blog: Claude 4 launch at Code with Claude - 22nd May 2025

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