Hi, I am somewhat novice to Perl world. I was trying to write a sub which takes Hash as reference and populate the hash (passed as reference). But when I try to dump the data of the Hash I didn't get any output. Below is the code which I tried to do so 
use strict;
use warnings;
use Data::Dumper;

sub PopulateHash {
    my $hashParm = shift;
    my %hash1 = %$hashParm;
    %hash1 = ( 
                1 => 'a',
                2 => 'b',
                3 => 'c',
                4 => 'd');
    print Dumper(\%hash1);
}

my %hash = ();
PopulateHash(\%hash);
print Dumper(\%hash);

[download]
The output of above code is given below 
$VAR1 = {
          '4' => 'd',
          '1' => 'a',
          '3' => 'c',
          '2' => 'b'
        };
$VAR1 = {};

[download]
As this hash will be used at many places so I don't want to have a copy to avoid overheads. Any pointers about where I am missing will be great.

In reply to Populating Hash passed to a sub as reference by techman2006

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