The GCD of 3 and 5 is 10
-- main::(gcd.pl:18)
die sprintf "Need two integer arguments, got %d", scalar(@ARGV) unless 
    @ARGV == 2;
x1 main::(gcd.pl:9)
    my ($a, $b) = @_;
*** We are not stopped at a return
<- main::(gcd.pl:21) main::gcd
printf "The GCD of %d and %d is %d\n", $a, $b, gcd($a, $b);
Return array value for main::gcd is:
1

Return array value set to:
10