Hello IvanAK,

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Here is a subroutine that may be helpful:

sub show_ref
{
    use Data::Dump 'pp';
    my $ref = shift;
    print "Reference to: ", ref($ref), "\n";
    print "Contents:     ",  pp($ref), "\n";
}

[download]

With this subroutine, you can easily see what any reference is, and what it contains. For example:

my $commissions = $sales->{tuesday}{jim};
show_ref($commissions);

[download]

gives:

14:11 >perl 879_SoPW.pl
Reference to: ARRAY
Contents:     [3, 8]

14:11 >

[download]

which shows that $commissions is a reference to an array which contains the elements 3 and 8.

Here tuesday is a hash or reference

No, “tuesday” is a hash key, and therefore it is a string (because in Perl, hash keys can only be strings). A hash contains key-value pairs, and in this case the value paired with the key “tuesday” is a reference to a hash. So show_ref($sales->{tuesday}); gives:

14:11 >perl 879_SoPW.pl
Reference to: HASH
Contents:     { jim => [3, 8], mary => [5, 5] }

14:25 >

[download]

Hope that helps,

Athanasius <°(((>< contra mundum Iustus alius egestas vitae, eros Piratica,

In reply to Re^2: Hash of Hash by Athanasius
in thread Hash of Hash by IvanAK

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