Hey YuckFoo. Ready for context? Here goes...

I'm getting a hashref from a DB_File, and unfreezing the data structure contained within with Storable. Then I traverse a user-defined path in the hashref and set a key in it, and it'll eventually get frozen back to the DB_File. An added complication (one that I should have mentioned, with hindsight :() is that if the full path doesn't exist, I have to create all the hashrefs leading up to the end - whilst still preserving everything that was in the original data structure. Here's a literal chunk of code from what I have.

    # the first element of $path is always a key in the DB_File
    my ($root, $tip) = (shift(@path), pop(@path));
    
    # get old tree
    my $old = thaw($db{$root});
    
    # start off at the root
    $nodule = $old;
    
    while (my $next_key = shift @path) {
        unless (exists $nodule->{$next_key}) {
            $nodule->{$next_key} = {};    
        }
        $nodule = $nodule->{$next_key};
    }
    
    $nodule->{$tip} = $content;
    print Dumper($old);

[download]

The thing is, when I print $old with Data::Dumper, I would expect it to be a structure looking like this (given that @path = ('foo', 'bar'), $tip = 'baz' and $content = 'some arbitrary data'):

$VAR1 = {foo =>
        {bar =>
            {baz => 'some arbitrary data'}
        }
    };

[download]

Instead it looks like:

$VAR1 = undef;

So that's what I want to achieve, and the example I gave in the question seems to be lose context in this environment, when by all rights it should work. Damn real life.



--
my one true love

In reply to Re: Re: descending a tree of hash references by Amoe
in thread descending a tree of hash references by Amoe

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