As I see it, this has little to do with hashes at all. Simply put it is a bit like trying to declare two variables thus:

my ($a,$b)=(25,$a/5);
print "$a and $b\n";

Hopefully that looks immediately wrong. For the reasons everyone has indicated above.

Sorry, I was using this as an opportunity to approach answering questions in a simple fashion, some day I may have to teach Java Developers how to program (a real language)?.

--

Brother Frankus.