it isnt as much magical as it is prototyping. 
use strict;
use warnings;
my %list=("bob" =>123,
          "tom" => "CAT");
sub change(\%){
    my $temp = shift;
    foreach (keys %$temp){
        print $_. " = $$temp{$_}\n";
        $$temp{$_} .= "hello";
    }
}
change (%list);
foreach (keys %list){
    print "$_ = $list{$_}\n";
}

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declaring the subroutine as sub change(\%){ will send the values as a reference

In reply to Re^3: referances of hashes, and subroutines by zer
in thread referances of hashes, and subroutines by tempest

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