zeroclickinfo-goodies/lib/DDG/Goodie/Regexp.pm

100 lines
2.8 KiB
Perl

package DDG::Goodie::Regexp;
# ABSTRACT: Parse a regexp and list the matches
use strict;
use warnings;
use DDG::Goodie;
use Safe;
zci answer_type => "regexp";
zci is_cached => 1;
triggers start => 'regex', 'match', 'regexp';
triggers any => '=~';
sub compile_re {
my ($re, $modifiers, $compiler) = @_;
$compiler->($re, $modifiers);
}
# Using $& causes a performance penalty, apparently.
sub get_full_match {
return html_enc(substr(shift, $-[0], $+[0] - $-[0]));
}
# Ensures that the correct numbered matches are being produced.
sub real_number_matches {
my ($one, @numbered) = @_;
# If the first match isn't defined then neither are the others!
return defined $one ? @numbered : ();
}
sub get_match_record {
my ($regexp, $str, $modifiers) = @_;
my $compiler = Safe->new->reval(q { sub { qr/(?$_[1])$_[0]/ } }) or return;
BEGIN {
$SIG{'__WARN__'} = sub {
warn $_[0] if $_[0] !~ /Use of uninitialized value in regexp compilation/i;
}
}
my @numbered = $str =~ compile_re($regexp, $modifiers, $compiler) or return;
@numbered = real_number_matches($1, @numbered);
my $matches = {};
$matches->{'Full Match'} = get_full_match($str);
foreach my $match (keys %+) {
$matches->{"Named Capture <$match>"} = html_enc($+{$match});
};
my $i = 1;
foreach my $match (@numbered) {
$matches->{"Subpattern Match $i"} = html_enc($match);
$i++;
};
return $matches;
}
my $regex_re = qr/\/(?<regex>.+)\/(?<modifiers>i)?/;
sub extract_regex_text {
my $query = shift;
$query =~ /^(?<text>.+) =~ $regex_re$/;
($+{regex} && $+{text}) || ($query =~ /^(?:match\s*regexp?|regexp?)\s*$regex_re\s+(?<text>.+)$/);
return unless defined $+{regex} && defined $+{text};
my $modifiers = $+{modifiers} // '';
return ($+{regex}, $+{text}, $modifiers);
}
sub get_match_keys { return sort (keys %{$_[0]}) }
handle query => sub {
my $query = $_;
my ($regexp, $str, $modifiers) = extract_regex_text($query) or return;
my $matches = get_match_record($regexp, $str, $modifiers) or return;
my @key_order = get_match_keys($matches);
return unless $matches->{'Full Match'} ne '';
return $matches,
structured_answer => {
data => {
title => "Regular Expression Match",
subtitle => html_enc("Match regular expression /$regexp/$modifiers on $str"),
record_data => $matches,
record_keys => \@key_order,
},
meta => {
signal => 'high',
},
templates => {
group => 'list',
options => {
content => 'record',
},
moreAt => 0,
},
};
};
1;