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Perl: accessing reference to variable inside hash.

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

Below is hash which contains reference to variables:

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

This works:

    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.
    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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