Right off the bat you've got a problem before you even start on your question. Your sub hash period's key 20050824 has duplicate values for the same key (to). That either needs to be an arrayref (to => [ 'new york', 'london' ]), or you need to rethink your data structure some.

In reply to Re: Expanding / flattening a structure by Fletch
in thread Expanding / flattening a structure by jaa

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