You're going to run into problems with the second block of code you posted.

You treat $hash{$key1}{$key2} as having a scalar, string value (for use as a hash key): 

my $key3 = $hash{$key1}{$key2};

[download]

Then in the next line you treat the same value as a hash reference: 

my $value = $hash{$key1}{$key2}{$key3};

[download]

You are effectively working on two different data structures: 

%hash = ( key1 => { key2 => $some_key } );
%hash = ( key1 => { key2 => { $some_key => $some_value } } );

[download]

-- Ken

In reply to Re: Hash of Hashes: Get the next Key without foreach loop by kcott
in thread Hash of Hashes: Get the next Key without foreach loop by snape

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