Yeah sorry I missed that requirement.

The OP wasn't really a SSCCE tho. Duplicated keys would have shown the problem. :)

Personally I would go for a clear 2 line approach, all this dereferencing doesn't make it more readable.

Or to repeat my old mantra:

• Perl would be better of with autobox-methods¹ {%A, %Z}->keys

On a side note: I always have the feeling that a big deal of perl4's appeal got lost with my, because of conceptual problems.

Hmm...People will misunderstand this.

What I mean is that many things are elegantly solved if you don't need 'my'. A language design problem.

¹) compare autobox