Re: How to define a list of regular expressions?

And, to avoid looping through all the regexes, it's possible to combine the individual regexes into a single regex (probably a big performance win if there are many regexes):

>perl -wMstrict -le
"my @regexes = (
   qr{ foo }xms,  qr{ bar }xms,  qr{ baz }xms,
   );
 my $any_regex = qr{ @{[ join '|', @regexes ]} }xms;
 for my $file (@ARGV) {
   print $file, $file =~ $any_regex ? ' MATCHES' : ' no match';
   }
"  xfooy  snork  bar
xfooy MATCHES
snork no match
bar MATCHES
[download]

Remember, however, that Perl's | (vertical bar) regex alternation operator provides ordered alternation: the overall alternation will match with whatever sub-pattern first matches in the alternation sequence, regardless of length. See Matching this or that in perlretut.

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Re^2: How to define a list of regular expressions? by poolpi (Hermit) on Jul 02, 2009 at 07:32 UTC
See Regexp::Assemble `#!/usr/bin/perl use strict; use warnings; use Regexp::Assemble; my $ra = Regexp::Assemble->new->add(qw[foo bar baz]); print $ra->re, "\n"; for (qw[xfooy snork bar]) { print " $_ does " . ( /$ra/ ? '' : 'not ' ) . "match\n"; } __END__ Output: (?-xism:(?:ba[rz]\|foo)) xfooy does match snork does not match bar does match` [download] hth, PooLpi 'Ebry haffa hoe hab im tik a bush'. Jamaican proverb	[reply] [d/l]

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Re^2: How to define a list of regular expressions?
by poolpi (Hermit) on Jul 02, 2009 at 07:32 UTC

See Regexp::Assemble

#!/usr/bin/perl 
use strict;
use warnings;
use Regexp::Assemble;


my $ra = Regexp::Assemble->new->add(qw[foo bar baz]);
print $ra->re, "\n";

for (qw[xfooy snork bar]) {
    print " $_ does " . ( /$ra/ ? '' : 'not ' ) . "match\n";
}

__END__

Output:

(?-xism:(?:ba[rz]|foo))
 xfooy does match
 snork does not match
 bar does match
[download]

hth,
PooLpi

'Ebry haffa hoe hab im tik a bush'. Jamaican proverb

[reply]
[d/l]