The only way to tell is to time your approach against any of the alternatives. The most obvious alternative would be --of course-- to run your regex-match in a loop and checking each alternative separately.

My feeling however is that this will be much slower.

Another alternative would be to hand-craft the regex by taking into account the same or similar chunks in each of the alternatives. The writing of the regex will take much more time and I'm not sure if such a more elaborate (but shorter) regex will work faster than a simple bunch of alternatives.

CountZero

"If you have four groups working on a compiler, you'll get a 4-pass compiler." - Conway's Law

In reply to Re: pattern matching with large regex by CountZero
in thread pattern matching with large regex by Anonymous Monk

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