Well, there is a lot happening in the two pieces of code, so it is hard to say for sure what is making the second version faster. But one thing you have improved is replacing all that array copying with splicing. Even better would be to manipulate just indices of the single @lines array for your computations.

-Mark

In reply to Re: A very odd happening (at least. . . to me) by kvale
in thread Processing large files many times over by dimmesdale

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