if key1 didn't exist - it pops into existence. This is a process called autovivification

I always wondered what the design decision behind this autovivification behaviour with mere existence testing had been...  I mean why does Perl not simply do a short-circuit evaluation from left to right, stopping as soon as a hash key does not exist?  In the example, key2 can't possibly exist if there is no hash referenced via key1 at all, because there is not even a key1. So why proceed any further?

In reply to Re^2: Best Multidimensional Hash Practices? by almut
in thread Best Multidimensional Hash Practices? by DamianKaelGreen

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