I wrote a subroutine that returns a string when it succeeds, but a negative integer when it "fails". The integer changes depending on which failure occurred. My question: is there a better way to check if the sub failed than what I have below (ofc without throwing a warning)? 
use strict;
use warnings;

for(my $ii = 1; $ii < 4; $ii++)
{
        my $a = foo($ii);
        if($a =~ /\d/)
        {
                print "Fail occured with code: $a\n";
        }
        else
        {
                print "Success\n";
        }
}

sub foo
{
        my $num = shift;

        if($num == 1)
        {
                return -1;
        }
        elsif($num == 2)
        {
                return -2;
        }
        else
        {
                return "true\n";
        }
}

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In reply to return from subfunction by fidesachates

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