Regexp::Common::balanced.3pm

Langue: en

Autres versions - même langue

Version: 2003-03-23 (mandriva - 01/05/08)

Section: 3 (Bibliothèques de fonctions)

Sommaire

NAME

Regexp::Common::balanced -- provide regexes for strings with balanced parenthesized delimiters or arbitrary delimiters.

SYNOPSIS

     use Regexp::Common qw /balanced/;
 
 

     while (<>) {
         /$RE{balanced}{-parens=>'()'}/
                                    and print q{balanced parentheses\n};
     }

DESCRIPTION

Please consult the manual of Regexp::Common for a general description of the works of this interface.

Do not use this module directly, but load it via Regexp::Common.

$RE{balanced}{-parens}


$RE{balanced}{-parens}

Returns a pattern that matches a string that starts with the nominated opening parenthesis or bracket, contains characters and properly nested parenthesized subsequences, and ends in the matching parenthesis.

More than one type of parenthesis can be specified:

         $RE{balanced}{-parens=>'(){}'}

in which case all specified parenthesis types must be correctly balanced within the string.

If we are using C{-keep} (See Regexp::Common):

$1
captures the entire expression

$RE{balanced}{-begin => "begin"}{-end => "end"}


$RE{balanced}{-begin => ``begin''}{-end => ``end''}

Returns a pattern that matches a string that is properly balanced using the begin and end strings as start and end delimiters. Multiple sets of begin and end strings can be given by separating them by "|"s (which can be escaped with a backslash).

     qr/$RE{balanced}{-begin => "do|if|case"}{-end => "done|fi|esac"}/

will match properly balanced strings that either start with do and end with done, start with if and end with fi, or start with case and end with esac.

If -end contains less cases than -begin, the last case of -end is repeated. If it contains more cases than -begin, the extra cases are ignored. If either of -begin or -end isn't given, or is empty, -begin => '(' and -end => ')' are assumed.

If we are using C{-keep} (See Regexp::Common):

$1
captures the entire expression

HISTORY

  $Log: balanced.pm,v $
  Revision 2.101  2003/02/01 22:55:31  abigail
  Changed Copyright years
 
 

  Revision 2.100  2003/01/21 23:19:40  abigail
  The whole world understands RCS/CVS version numbers, that 1.9 is an
  older version than 1.10. Except CPAN. Curse the idiot(s) who think
  that version numbers are floats (in which universe do floats have
  more than one decimal dot?).
  Everything is bumped to version 2.100 because CPAN couldn't deal
  with the fact one file had version 1.10.
 
 

  Revision 1.6  2002/08/20 15:20:48  abigail
  Documented -begin and -end
 
 

  Revision 1.5  2002/08/08 23:57:33  abigail
  Added HISTORY section.
 
 

  Revision 1.4  2002/08/08 23:53:54  abigail
  Reworked and extended $RE{balanced}. It now takes multiple arbitrary
  length delimiters. -parens is just a short-cut for some of the common,
  simpler cases.
 
 

  Revision 1.3  2002/08/05 12:16:58  abigail
  Fixed 'Regex::' and 'Rexexp::' typos to 'Regexp::'
  (Found my Mike Castle).
 
 

  Revision 1.2  2002/07/25 22:37:44  abigail
  Added 'use strict'.
  Added 'no_defaults' to 'use Regexp::Common' to prevent loaded of all
  defaults.
 
 

  Revision 1.1  2002/07/25 22:14:44  abigail
  Factored out from Regexp::Common.

SEE ALSO

Regexp::Common for a general description of how to use this interface.

AUTHOR

Damian Conway (damian@conway.org)

MAINTAINANCE

This package is maintained by Abigail (regexp-common@abigail.nl).

BUGS AND IRRITATIONS

Bound to be plenty.

For a start, there are many common regexes missing. Send them in to regexp-common@abigail.nl.

      Copyright (c) 2001 - 2003, Damian Conway. All Rights Reserved.
        This module is free software. It may be used, redistributed
       and/or modified under the terms of the Perl Artistic License
             (see http://www.perl.com/perl/misc/Artistic.html)