Can you back up your assertion that reving up the regexp engine has a significant slowdown compared to non-regexp alternatives?

My understanding is that the regular expression engine will recognize when a regular expression just searches for a constant string and switches to the same Boyer-Moore optimization that index uses. Solutions like unpack can win because they get rid of having loops written in Perl. Not because they walk through the string significantly faster.

Yes, there is overhead to regular expressions, but it is truly marginal.

In reply to Re: Re: Re: Re: Need to process a tab delimted file *FAST* by tilly
in thread Need to process a tab delimted file *FAST* by devnul

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