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Regexp::Common::balancUserpContributed Perl DocumRegexp::Common::balanced(3pm)

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}
       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.

       Since version 2013030901, $1 will always be set (to the entire matched
       substring), regardless whether "{-keep}" is used or not.

   $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.

       Since version 2013030901, $1 will always be set (to the entire matched
       substring), regardless whether "{-keep}" is used or not.

   Note
       Since version 2013030901 the pattern will make of the recursive
       construct "(?-1)", instead of using the problematic "(??{ })"
       construct.  This fixes an problem that was introduced in the 5.17
       development track.

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

AUTHOR
       Damian Conway (damian AT conway.org)

MAINTENANCE
       This package is maintained by Abigail (regexp-common AT abigail.be).

BUGS AND IRRITATIONS
       Bound to be plenty.

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

LICENSE and COPYRIGHT
       This software is Copyright (c) 2001 - 2017, Damian Conway and Abigail.

       This module is free software, and maybe used under any of the following
       licenses:

        1) The Perl Artistic License.     See the file COPYRIGHT.AL.
        2) The Perl Artistic License 2.0. See the file COPYRIGHT.AL2.
        3) The BSD License.               See the file COPYRIGHT.BSD.
        4) The MIT License.               See the file COPYRIGHT.MIT.

perl v5.24.1                      2017-06-17     Regexp::Common::balanced(3pm)