exists doesn't autovivify. 

>perl -le "my %hash; exists($hash{foo}); print scalar %hash"
0

[download]

Dereferencing (->) does. 

>perl -le "$hash->{foo}; print $hash ? 1 : 0"
1

[download]

In reply to Re: Why does exists cause autovivication? by ikegami
in thread Why does exists cause autovivication? by Argel

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