This is a special case, because for some reason the two set of keys are guaranteed to uniquely identify the data structures behind them ( they are alternative descriptions of the same data ). They are constructed in such a way, that there can be no overlap ( in fact this takes quite a bit of effort, but ultimately it is done in a foolproof way ). It depends on the circumstances which set of keys is more convenient to access the data elements.

In reply to Re^3: How can one change the keys of a hash to an alternative set of keys? by tkguifan
in thread How can one change the keys of a hash to an alternative set of keys? by tkguifan

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