From exists:

Although the most deeply nested array or hash element will not spring into existence just because its existence was tested, any intervening ones will.

This is called autovivification. There is a good explanation of autovivification at http://sysarch.com/Perl/autoviv.txt.

Hope that helps,

Athanasius <°(((>< contra mundum

In reply to Re: I just want to understand why ... by Athanasius
in thread Why does testing for the existence of hash keys create the keys ? by fshrewsb

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