No, wrong. You want to compare the average and total speed of insertion before and after that undef(%foobar) operation. This is clearly something I'd use Benchmark for. Perhaps there's some big time hit when the hash is first re-used but it goes away as the hash is used more.

In reply to Re^3: Use of undef slowing down perl? by diotalevi
in thread Use of undef slowing down perl? by thalej

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