Hi All,

I need to compare two hashes and generate the union of these hashes.

The below code updated the h1 hash also. But i don't want to update h1 hash. So kindly correct me where i made wrong.

$h1 = {
    'drug comparison' => 
    {
          '7003000.xml' => {
                             'entity' => 'a1, a2, a3'
                           },
          '70037559.xml' => {
                              'entity' => 'x1, x2, x3'
                            }
        }
};

$h2 = {
    'drug comparison' => 
    {
          '7004562.xml' => {
                             'entity' => 'z1, z2, z3'
                           },
          '70037559.xml' => {
                              'entity' => 'e1, e2, e3'
                            }
        }
};
$h3 = union_of_h1_h2 ($h1, $h2);
print $h3;


sub union_of_h1_h2 {
    my ($ai, $reference) = @_;
    my %output = %$ai;
    my %ref = %$reference;
        
    foreach my $_ref (keys %ref) {
        unless (exists $output{$_ref}) {
            $output{$_ref} = $ref{$_ref};
        }else {
            foreach my $filename (keys %{$ref{$_ref}}) {
                if (!exists $output{$_ref}{$filename}) {
                    $output{$_ref}{$filename} = $ref{$_ref}{$filename}
+;
                }
            }
        }
    }
    return \%output;
}

[download]


I need the output hash h3 should be 

$h3 = {
    'drug comparison' => 
    {
          '7003000.xml' => {
                             'entity' => 'a1, a2, a3'
                           },
          '70037559.xml' => {
                              'entity' => 'x1, x2, x3'
                            },
          '7004562.xml' => {
                             'entity' => 'z1, z2, z3'
                           }
        }
};

[download]


Thanks in advance,
Shanmugam A.

In reply to Generate union of the two hashes by shan_emails

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