Juts FYI: In Perl 5.10 alternations not containing regex metachars will not backtrack at all as they are represented by a trie node that can traverse all of the alternations in a single pass. Id say which version of perl contains this but embarrasingly I appear to have forgotten.

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$world=~s/war/peace/g

In reply to Re^3: Efficient code. by demerphq
in thread Efficient code. by murugu

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