Hi,

This is probably easy, but I have a mental block. I have a big unwieldy hash that I want to operate on at a certain key nest depth. I want to loop through some update records, access the appropriate sub-hash, use a very short local variable to reference said sub-hash, munge the data, and have the original hash update as I update the short local variable (a reference, I'd think). The following code doesn't work, but I think conveys the essence of what I want (that is, I want %a to have $a{'WI'}{'GreenBay'}{'Color'} equal to 'White'): 
use Data::Dumper;

my %a;
$a{'WI'}{'GreenBay'}{'Color'} = 'Black';

foreach my $update ("WI,GreenBay,White") {
    my ($state,$city,$color) = split /,/, $updtate;
    my $h = \$a{$state}{$city};
    $h->{'Color'} = $color;
};

print Dumper(\%a), "\n";

[download]
Is there a similar way of doing this that allows me to assign an inner hash to a local reference and operate on the reference to modify the original hash?

Thanks, Matt

Note: example keys inspired by watching tonight's Monday Night Football.

In reply to Reference/Alias inner hash section by mpettis

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