A very valuable tool is Data::Dumper that let's you inspect the contents of variables. In your case: 

use Data::Dumper;
print Dumper \%hash;

[download]

will show you that the two scenarios are not the same.

With Data::Dumper you can figure out most of these kind of questions.

In reply to Re: autovivication and referencing by hdb
in thread autovivication and referencing by Amblikai

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