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Re: I just want to understand why ...

by Athanasius (Chancellor)
on Oct 08, 2012 at 08:18 UTC ( #997764=note: print w/replies, xml ) Need Help??


in reply to Why does testing for the existence of hash keys create the keys ?

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

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