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Perl: accessing reference to variable inside hash.


 
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# 1  
Old 07-03-2012
Perl: accessing reference to variable inside hash.

Below is hash which contains reference to variables:

Code:
my %mandatoryFields = (
                    1  => \$msgtype,
                    2  => \$switchtype,
                    3  => \$card_nbr,
                    4  => \$natv_tran_type_code,
                    5  => \$amt_1
);


This works:

Code:
    foreach my $field (keys %mandatoryFields) {

        my $value = $mandatoryFields{$field};

        unless ($$value) {

#      do something
        }
    }



This dosen't: WHY ? The code never gets inside the unless block even though any variable inside the hash is undefined.
Code:
    foreach my $field (keys %mandatoryFields) {

        unless ($$mandatoryFields{$field}) {

#      do something
        }
    }


Last edited by som.nitk; 07-03-2012 at 09:01 AM..

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