Let's say I have the following hash entries: 
$hash->{'A'}->{'B5'}->{'C'} = 123;
$hash->{'A'}->{'B5'}->{'D'} = 103;
$hash->{'A'}->{'B2'}->{'C'} = 101;

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I'd like to query the hash, but all I am given for inputs for queries are just values for the first two keys. Some examples: A/B5, A/B9, C/B2. If there's a hit (eg A/B5), then I could ask for the keys and iterate through that subhash.

My (limited) understanding of a hash is that for a 3-tier hash like this, you must always provide all 3 keys to get to test for existence.

I thought of 
if (exists $hash->{'A'}->{'B2'}) ...

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but I don't think that would work, as Perl would think that's another hash enitrely.
Or maybe something like 
$hash->{'A'}->{'B2'}->{*}

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Is there a way to do this without iterating through the levels of the HoH?

Thanks.

In reply to Hash of hash: testing for existence of higher level key (only) by zuma53

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