Actually I stand corrected: the fixed string prefixes are collected together into a trie where there are (possibly differing) wildcard suffixes; the killer is the individual captures, which disables the trie optimisation.

So, alternation is the fastest, as long as you put any captures outside the alt.

Dave.

In reply to Re^3: alternation in regexes: to use or to avoid? by dave_the_m
in thread alternation in regexes: to use or to avoid? by dk

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