Perl: if ( element in list )

Question

I\'m looking for presence of an element in a list.

In Python there is an in keyword and I would do something like:

if element in list:
            


        

Answer 1

If you plan to do this many times, you can trade-off space for lookup time:

#!/usr/bin/perl

use strict; use warnings;

my @array = qw( one ten twenty one );
my %lookup = map { $_ => undef } @array;

for my $element ( qw( one two three ) ) {
    if ( exists $lookup{ $element }) {
        print "$element\n";
    }
}

assuming that the number of times the element appears in @array is not important and the contents of @array are simple scalars.