As a general proposition, avoiding using unnecessary captures is a Good Thing.

Also as a general proposition, optimisation should be avoided until it becomes obvious that it is unavoidable.

use re 'debug' can tell you a lot about what's going on -- getting a trace of what happens on some real data can be quite instructive. YAPE::Regex::Explain is reputed to be useful, but it does look a little old -- other monks may be able to advise.

One thing that can really slow down regex is back-tracking. The more specific the matching elements, the less opportunity you give for backtracking, the better. Note that a floating start to a regex is an excellent way of triggering a lot of backtracking !

In reply to Re: Speeding up a large regex match pattern by gone2015
in thread Speeding up a large regex match pattern by wossname

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