1 package Regexp::Wildcards;
6 use Text::Balanced qw/extract_bracketed/;
10 Regexp::Wildcards - Converts wildcard expressions to Perl regular expressions.
18 our $VERSION = '0.03';
22 use Regexp::Wildcards qw/wc2re/;
25 $re = wc2re 'a{b.,c}*' => 'unix'; # Do it Unix style.
26 $re = wc2re 'a.,b*' => 'win32'; # Do it Windows style.
27 $re = wc2re '*{x,y}.' => 'jokers'; # Process the jokers & escape the rest.
31 In many situations, users may want to specify patterns to match but don't need the full power of regexps. Wildcards make one of those sets of simplified rules. This module converts wildcard expressions to Perl regular expressions, so that you can use them for matching. It handles the C<*> and C<?> jokers, as well as Unix bracketed alternatives C<{,}>, and uses the backspace (C<\>) as an escape character. Wrappers are provided to mimic the behaviour of Windows and Unix shells.
37 This function takes as its only argument the wildcard string to process, and returns the corresponding regular expression according to standard Unix wildcard rules. It successively escapes all unprotected regexp special characters that doesn't hold any meaning for wildcards, turns jokers into their regexp equivalents, and changes bracketed blocks into C<(?:|)> alternations. If brackets are unbalanced, it will try to substitute as many of them as possible, and then escape the remaining C<{> and C<}>. Commas outside of any bracket-delimited block will also be escaped.
39 # This is a valid bracket expression, and is completely translated.
40 print 'ok' if wc2re_unix('{a{b,c}d,e}') eq '(?:a(?:b|c)d|e)';
42 The function handles unbalanced bracket expressions, by escaping everything it can't recognize. For example :
44 # The first comma is replaced, and the remaining brackets and comma are escaped.
45 print 'ok' if wc2re_unix('{a\\{b,c}d,e}') eq '(?:a\\{b|c)d\\,e\\}';
47 # All the brackets and commas are escaped.
48 print 'ok' if wc2re_unix('{a{b,c\\}d,e}') eq '\\{a\\{b\\,c\\}d\\,e\\}';
54 return unless defined $re;
55 $re =~ s/(?<!\\)((?:\\\\)*[^\w\s?*\\\{\},])/\\$1/g;
56 return do_bracketed(do_jokers($re));
61 Similar to the precedent, but for Windows wildcards. Bracketed blocks are no longer handled (which means that brackets will be escaped), but you can provide a comma-separated list of items.
63 # All the brackets are escaped, and commas are seen as list delimiters.
64 print 'ok' if wc2re_win32('{a{b,c}d,e}') eq '(?:\\{a\\{b|c\\}d|e\\})';
70 return unless defined $wc;
71 $wc =~ s/(?<!\\)((?:\\\\)*[^\w\s?*\\,])/\\$1/g;
72 my $re = do_jokers($wc);
73 if ($re =~ /(?<!\\)(?:\\\\)*,/) { # win32 allows comma-separated lists
74 $re = '(?:' . do_commas($re) . ')';
79 =head2 C<wc2re_jokers>
81 This one only handles the C<?> and C<*> jokers. All other unquoted regexp metacharacters will be escaped.
83 # Everything is escaped.
84 print 'ok' if wc2re_jokers('{a{b,c}d,e}') eq '\\{a\\{b\\,c\\}d\\,e\\}';
90 $wc =~ s/(?<!\\)((?:\\\\)*[^\w\s?*\\])/\\$1/g;
91 return do_jokers($wc);
96 A generic function that wraps around all the different rules. The first argument is the wildcard expression, and the second one is the type of rules to apply, currently either C<unix>, C<win32> or C<jokers>. If the type is undefined, it defaults to C<unix>.
101 'jokers' => \&wc2re_jokers,
102 'unix' => \&wc2re_unix,
103 'win32' => \&wc2re_win32
107 my ($wc, $type) = @_;
108 return unless defined $wc;
110 return $types{lc $type}($wc);
115 These four functions are exported only on request : C<wc2re>, C<wc2re_unix>, C<wc2re_win32> and C<wc2re_jokers>.
119 use base qw/Exporter/;
122 our @EXPORT_OK = ('wc2re', map { 'wc2re_' . $_ } keys %types);
123 our @EXPORT_FAIL = qw/extract do_jokers do_commas do_brackets do_bracketed/;
124 our %EXPORT_TAGS = ( all => [ @EXPORT_OK ] );
128 L<Text::Balanced>, which is bundled with perl since version 5.7.3
132 Some modules provide incomplete alternatives as helper functions :
134 L<Net::FTPServer> has a method for that. Only jokers are translated, and escaping won't preserve them.
136 L<File::Find::Match::Util> has a C<wildcard> function that compiles a matcher. It only handles C<*>.
138 L<Text::Buffer> has the C<convertWildcardToRegex> class method that handles jokers.
142 Vincent Pit, C<< <perl at profvince.com> >>
146 Please report any bugs or feature requests to
147 C<bug-regexp-wildcards at rt.cpan.org>, or through the web interface at
148 L<http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Regexp-Wildcards>.
149 I will be notified, and then you'll automatically be notified of progress on
150 your bug as I make changes.
154 You can find documentation for this module with the perldoc command.
156 perldoc Regexp::Wildcards
158 =head1 COPYRIGHT & LICENSE
160 Copyright 2007 Vincent Pit, all rights reserved.
162 This program is free software; you can redistribute it and/or modify it
163 under the same terms as Perl itself.
167 sub extract { extract_bracketed shift, '{', qr/.*?(?:(?<!\\)(?:\\\\)*)(?={)/; }
171 # escape an odd number of \ that doesn't protect a regexp/wildcard special char
172 s/(?<!\\)((?:\\\\)*\\(?:[\w\s]|$))/\\$1/g;
173 # substitute ? preceded by an even number of \
174 s/(?<!\\)((?:\\\\)*)\?/$1./g;
175 # substitute * preceded by an even number of \
176 s/(?<!\\)((?:\\\\)*)\*+/$1.*/g;
182 # substitute , preceded by an even number of \
183 s/(?<!\\)((?:\\\\)*),/$1|/g;
189 substr $rest, 0, 1, '';
191 my ($re, $bracket, $prefix) = ('');
192 while (($bracket, $rest, $prefix) = extract $rest and $bracket) {
193 $re .= do_commas($prefix) . do_brackets($bracket);
195 $re .= do_commas($rest);
196 return '(?:' . $re . ')';
201 my ($re, $bracket, $prefix) = ('');
202 while (($bracket, $rest, $prefix) = extract $rest and $bracket) {
203 $re .= $prefix . do_brackets($bracket);
206 $re =~ s/(?<!\\)((?:\\\\)*[\{\},])/\\$1/g;
210 1; # End of Regexp::Wildcards