I hate to question someone's credentials, but for my $key (keys %hash) { ... } or if it's a reference for my $key (keys %{$ref_to_hash}) { ... } Tha

I hate to question someone's credentials, but for my $key (keys %hash) { ... } or if it's a reference for my $key (keys %{$ref_to_hash}) { ... } That is fairly simple, and not a good example of something that is difficult in Perl. If you cannot keep that straight, I suspect the extent to which you really use Perl is limited.