Related to yesterday’s post, I just caught up on the comments to Peter Gurevich’s (MS IE Performance PM) guidance to avoid using closures in IE. Matt Kruse had a perfect, concise response which I feel compelled to quote here verbatim:

Closures don’t cause memory leaks.

Browsers that have garbage collection bugs (IE6) and continue to retain those bugs in new versions (IE7) cause memory leaks.

Closures are an extremely powerful and useful programming technique. It’s unfortunate that you would recommend against their use simply because your browser has a bug that causes a memory leak.

A huge amount of time has been spent by the js community to detect, resolve, and work around these IE memory leaks. It’s too bad this was required, and will continue to be required as long as MS refuses to fix the problem.

Hopefully IE’s market share will continue to drop and we can begin to ignore these memory leaks because every other browser out there handles closures just fine.