Simon Willison’s Weblog

Lazy Function Definition Pattern. Neat JavaScript trick: redefine a function the first time it’s called, for example to switch in different browser implementations based on object detection.

Posted 15th August 2007 at 6:57 pm

Recent articles

Useful patterns for building HTML tools - 10th December 2025
Under the hood of Canada Spends with Brendan Samek - 9th December 2025
Highlights from my appearance on the Data Renegades podcast with CL Kao and Dori Wilson - 26th November 2025

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