http://www.perlmonks.org?node_id=533936

asz has asked for the wisdom of the Perl Monks concerning the following question:

hello,

i recently had to use $', so reading perlvar more carefully, i noticed it warns about using $':
The use of this variable anywhere in a program imposes a considerable performance penalty on all regular expression matches. See "BUGS".
...but in the BUGS section it states that:
Due to an unfortunate accident of Perl's implementation, use English imposes a considerable performance penalty on all regular expression matches in a program,[...]
now i'm confused :) ... i don't understand wheter use English; (i.e. $POSTMATCH) reduces performance or simply using $'.
thank you for your time!

:)))))