Simon Willison’s Weblog

A Regular Expression Matcher: Code by Rob Pike, Exegesis by Brian Kernighan (via) Delightfully clear and succinct 30-line C implementation of a regular expression matcher that supports $, ^, . and * operations.

Posted 5th December 2017 at 6:36 pm

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OpenAI DevDay 2025 live blog - 6th October 2025
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Designing agentic loops - 30th September 2025

c 42 regular-expressions 13 rob-pike 2

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