SYNTAX

The use of $` , $& or $' will slow down all regex use within your program. Consult perlvar for @- to see equivalent expressions that won't cause slow down. See also Devel::SawAmpersand. Starting with Perl 5.10, you can also use the equivalent variables ${^PREMATCH} , ${^MATCH} and ${^POSTMATCH} , but for them to be defined, you have to specify the /p (preserve) modifier on your regular expression.