Thanks.
My initial confusion came from thinking that: 
my %source;
my %action;
my ($source, $action) = qw(test_source test_action);
$source{$source} = { $action{$action}++ }; 
$source{$source} = { $action{$action}++ };

[download]
would give me a hash called %source with each key having a value of the hash "%action", with it's keys and values.
It output: 
$VAR1 = 'test_source';
$VAR2 = {
          '1' => undef
        };
$VAR1 = 'test_action';
$VAR2 = '2';

where I was looking for: 
$VAR1 = 'test_source';
$VAR2 = {
          'test_action' => 2
        };
It makes Perl-fect sense, though, that it would set the value of $source{$action} to true, while setting the keys and values of %action_hash.

Thanks for helping me grok this.
  dug

In reply to Re: Re: Choosing the right datastructure by dug
in thread Choosing the right datastructure by dug

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