Simon Willison’s Weblog

JavaScript Closures for Dummies. Not quite for Dummies as it talks about C pointers, but a valiant attempt.

Posted 6th July 2006 at 10:01 am

Recent articles

The Summer of Johann: prompt injections as far as the eye can see - 15th August 2025
Open weight LLMs exhibit inconsistent performance across providers - 15th August 2025
LLM 0.27, the annotated release notes: GPT-5 and improved tool calling - 11th August 2025

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