A bit late to the game, but...

I think your benchmark is still flawed because you're applying a destructive operation multiple times without re-initializing the test data in between.

On the first iteration of each test case, the corresponding array contains multiple matches. After the first iteration, the matches are removed, so you're simply testing which method can remove zero matching elements the fastest. It makes sense that the splice approach will do this quickly, since splice is never actually called; while the grep approach, which needs to copy every element of the array, is not so fast.

In reply to Re^4: foreach array - delete current row ? (flaws) by Anonymous Monk
in thread foreach array - delete current row ? by JockoHelios

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