Perl - Check if any elements in each different array matches a variable

Question

I have a problem I am hoping someone can help with (greatly simplified for the purposes of explaining what I am trying to do)...

I have three different arrays:

my @array1 =  ("DOG","CAT","HAMSTER");
my @array2 =  ("DONKEY","FOX","PIG", "HORSE");
my @array3 =  ("RHINO","LION","ELEPHANT");

I also have a variable that contains the content from a web page (using WWW::Mechanize):

my $variable = $r->content;

I now want to see if any of the elements in each of the arrays are found in the variable, and if so which array it comes from:

e.g

if ($variable =~ (any of the elements in @array1)) {
     print "FOUND IN ARRAY1";
} elsif ($variable =~ (any of the elements in @array2)) { 
     print "FOUND IN ARRAY2";
} elsif ($variable =~ (any of the elements in @array3)) {
     print "FOUND IN ARRAY3";
}

What is the best way to go about doing this using the arrays and iterating through each element in the arrays? Is there a better way this can be done?

your help is much appreciated, thanks

Answer 1

You can make a regex out of the array elements, but you'll most likely want to disable meta characters and make sure you do not get partial matches:

my $rx = join('\b|\b', map quotemeta, @array1);

if ($variable =~ /\b$rx\b/) {
    print "matched array 1\n";
}

If you do want to get partial matches, such as FOXY below, simply remove all the \b sequences.

Demonstration:

use strict;
use warnings;

my @array1 =  ("DOG","CAT","HAMSTER");
my @array2 =  ("DONKEY","FOX","PIG", "HORSE");
my @array3 =  ("RHINO","LION","ELEPHANT");

my %checks = (
    array1 => join('\b|\b', map quotemeta, @array1),
    array2 => join('\b|\b', map quotemeta, @array2),
    array3 => join('\b|\b', map quotemeta, @array3),
);

while (<DATA>) {
    chomp;
    print "The string: '$_'\n";
    for my $key (sort keys %checks) {
        print "\t";
        if (/\b$checks{$key}\b/) {
            print "does";
        } else {
            print "does not";
        }
        print " match $key\n";
    }
}

__DATA__
A DOG ATE MY RHINO
A FOXY HORSEY

Output:

The string: 'A DOG ATE MY RHINO'
        does match array1
        does not match array2
        does match array3
The string: 'A FOXY HORSEY'
        does not match array1
        does not match array2
        does not match array3