The PDL modules have something like this: perl -MPDL -e '$in = pdl 0..100; $x = 10; print where ( $in, $in == $x )', or you could roll your own with something like this:

#!/usr/local/bin/perl

use warnings;
use strict;

sub in {
    my  ( $x, @args ) = @_;
    foreach ( @args ) { 
        return 1 if $_ == $x;
    }
    return 0;
}

print ( "\nyes: ", in (10, 8..12) );
print ( "\nno: ",  in (10, 11..120) )
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