You can achieve what you want using subroutine prototypes, so long as you predeclare them. You can learn more on the perlsub manpage. Look at the sections on "Pass By Reference" and "Prototypes".

When you say 

myroutine(%hash);

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then %hash is passed to myroutine() as a list. This means that in 
%hash = (
    'alpha' => 'alpher',
    'beta' => 'bethe',
    'gamma' => 'gamow');

myroutine(%hash);

sub myroutine {
print shift, "\n";
}

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will print, randomly, either 'alpha', 'beta', or 'gamma'. (In practice, it'll print 'gamma', but in principle the order is undetermined.)

stephen

In reply to Re: passing hashes and hash reference by stephen
in thread passing hashes and hash reference by symŽ

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