Also note that I dereferenced the hashref $json_hash{'results'} before using it, because it's not "stable" Perl code to call values() (or keys()) on a hashref. I imagine you got a warning like "values on reference is experimental at ...", no?

More than that, I seem to recall that this either already is deprecated and scheduled to be removed (though I can't find it in perldeprecation perldeprecation), or that deprecation was at the very least discussed. Warning or not I'd definitely not use keys and friends on a reference.

EDIT: found it. It's been removed in Perl 5.24; see perl5240delta.