your first version 'print 1 2 3' from the global hash hash. It works also fine without my ($hash)=@_; .
the second one can not print 1 2 3, since it want s to print from a hash, but your hash is a hashref. 
use strict;
use warnings; # ;-)

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Boris

In reply to Re: Reference curiosity? by borisz
in thread Reference curiosity? by tamaguchi

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