See Slow Regex - How to Optimize, noting in particular GrandFather's benchmark results of ikegami's solution.

The summary is: it's better to grab the first word and look it up in a hash than to use a big ol' alternation. If you can't parse out the word, though, you might want to look at Regexp::Optimizer or some such.

Caution: Contents may have been coded under pressure.

In reply to Re: large file and processing efficiency by Roy Johnson
in thread large file and processing efficiency by chiragshukla

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