[jdd]

The point of this test is to show that you should avoid making blanket assumptions about performance and that you shouldn't fear the RegExp :)

You can see my full reply here: http://jsperf.com/regexp-indexof-perf#comment-3

[WayneDB]

You're still testing concat + indexOf, not just indexOf. I think that test is broken.

[jdd]

The test isn't broken in the scope of its use case. You are totally missing the point which is RegExp's are no longer a guaranteed fail when it comes to performance and that in many situations, including that jsPerf test, can out perform the indexOf equivalent.

[WayneDB]

I think that a lot of people would just like to see a direct comparison, that's all.