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Sometimes, a comment will work just as well, without the overhead. Consider the following: local $/; # INPUT_RECORD_SEPARATORAs another option, in the documenation for 'English', there's a suggestion to use: use English qw( -no_match_vars ) ;to prevent the problems mentioned. As for the 'evil variables', the following note is in 'perldoc perlre': WARNING: Once Perl sees that you need one of $&, $`, or $' anywhere in the program, it has to provide them for every pattern match. This may substantially slow your program. Perl uses the same mechanism to produce $1, $2, etc, so you also pay a price for each pattern that contains capturing parentheses. (To avoid this cost while retaining the grouping behaviour, use the extended regular expression "(?: ... )" instead.) But if you never use $&, $` or $', then patterns without capturing parentheses will not be penalized. So avoid $&, $', and $` if you can, but if you can't (and some algorithms really appreciate them), once you've used them once, use them at will, because you've already paid the price. As of 5.005, $& is not so costly as the other two. In reply to Re^3: Pimp My RegEx
by jhourcle
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