=head1 SYNOPSIS
- use English qw( -no_match_vars ) ; # Avoids regex performance penalty
use English;
+ use English qw( -no_match_vars ) ; # Avoids regex performance penalty
+ # in perl 5.16 and earlier
...
if ($ERRNO =~ /denied/) { ... }
=head1 PERFORMANCE
+NOTE: This was fixed in perl 5.18. Mentioning these three variables no
+longer makes a speed difference. This section still applies if your code
+is to run on perl 5.16 or earlier.
+
This module can provoke sizeable inefficiencies for regular expressions,
due to unfortunate implementation details. If performance matters in
your application and you don't need $PREMATCH, $MATCH, or $POSTMATCH,