diff options
author | Zsban Ambrus <ambrus@math.bme.hu> | 2013-06-09 09:26:22 -0400 |
---|---|---|
committer | Ricardo Signes <rjbs@cpan.org> | 2013-06-09 09:32:09 -0400 |
commit | 9af0006bddac3108a478ad921119bb41c07b088e (patch) | |
tree | 1cab3b9b0088de5a6776bfd0a912efa3a07eae8f /pod/perl5100delta.pod | |
parent | e7245888eddac196db172b05d1c37f48debd2a10 (diff) | |
download | perl-9af0006bddac3108a478ad921119bb41c07b088e.tar.gz |
document the /p flag and related variables in delta
Diffstat (limited to 'pod/perl5100delta.pod')
-rw-r--r-- | pod/perl5100delta.pod | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/pod/perl5100delta.pod b/pod/perl5100delta.pod index 4e5c6d3a2b..10d71d686a 100644 --- a/pod/perl5100delta.pod +++ b/pod/perl5100delta.pod @@ -200,6 +200,23 @@ logically match their complements. C<\R> matches a generic linebreak, that is, vertical whitespace, plus the multi-character sequence C<"\x0D\x0A">. +=item Optional pre-match and post-match captures with the /p flag + +There is a new flag C</p> for regular expressions. Using this +makes the engine preserve a copy of the part of the matched string before +the matching substring to the new special variable C<${^PREMATCH}>, the +part after the matching substring to C<${^POSTMATCH}>, and the matched +substring itself to C<${^MATCH}>. + +Perl is still able to store these substrings to the special variables +C<$`>, C<$'>, C<$&>, but using these variables anywhere in the program +adds a penalty to all regular expression matches, whereas if you use +the C</p> flag and the new special variables instead, you pay only for +the regular expressions where the flag is used. + +For more detail on the new variables, see L<perlvar>; for the use of +the regular expression flag, see L<perlop> and L<perlre>. + =back =head2 C<say()> |