I mentioned a possible speed-up when 'unrolling' the regexp. Here's a small benchmark backing up that claim:
#!/usr/bin/perl use strict; use warnings; use Benchmark 'cmpthese'; our $re1 = qr /"([^"\\]|\\.)*"/; our $re2 = qr /"([^"\\]+|\\.)*"/; our $re3 = qr /"[^"\\]*(\\.[^"\\]*)*"/; chomp (our @data = <DATA>); cmpthese -5 => { plain => '/$re1/ for @data', unroll1 => '/$re2/ for @data', unroll2 => '/$re3/ for @data', }; __DATA__ A "red" fish A "red" fish and a "blue" fish The book is called "A 5\" dwarf" A backslash ("\\") and a forwardslash ("/") No delimiters here at all.

The results:

Rate plain unroll1 unroll2 plain 50621/s -- -20% -38% unroll1 63260/s 25% -- -22% unroll2 81507/s 61% 29% --

Abigail


In reply to Re: regex regexen by Abigail-II
in thread regex regexen by mooresan

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