in reply to passing hash to subroutine

You're kinda mixing up pass by value and pass by reference. If you want to pass by value, then</strike

In the method being invoked, you need to capture all the passed values, not just the the first one: 

chargeCard( %_billingInfo );
...
sub chargeCard {
  my %_billingInfo = @_;
  $_billingInfo{key}
}

[download]
but you'd probably be better of using a reference: 
chargeCard( \%_billingInfo );
...
sub chargeCard {
  my $_billingInfo = shift;
  $_billingInfo->{key};
}

[download]

-derby

update: Remove the whole passed by value/by ref. ikegami reminded me perl always passes by value and I was confusing *pass by reference* with *passing a reference.*

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