use strict;
use warnings;
use diagnostics;


sub isequal {
    return 0 if ( grep { ! defined( $_ ) } @_ ) != scalar @_;
    no warnings qw/uninitialized/;
    my %gadget;
    @gadget{ @_ } = ();
    return scalar keys %gadget == 1 ? 1 : 0;
}

my @test = (
    [ 0, 1 ],
    [ "1", "one" ],
    [ 0, "0" ],
    [ 0, undef ],
    [ 1, undef ],
    [ "hello", undef ],
    [ undef, undef ],
    [ 1, 1 ],
    [ "1", 1 ],
    [ "hello", "hello" ]
);

foreach my $items ( @test ) {
    my( $left, $right ) = @{ $items };
    my $comp = isequal( $left, $right );
    foreach( $left, $right ) {
        ! defined $_ and $_ = "undef";
    }
    print "Testing $left, $right == ", $comp ? "equal\n" : "not equal\n";
}