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

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Claude can write complete Datasette plugins now - 8th October 2025
Vibe engineering - 7th October 2025
OpenAI DevDay 2025 live blog - 6th October 2025

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