I have to wonder if exists could be patched to not have this behavior. Short-circuiting comes to mind.
It wouldn't be easy. By the time the exists op is called, all but one of the derefs has already taken place. IE exists is essentially a binary operator taking a hash and key as args: 
exists $hash{a}{b}{c}

[download]
is executed as: 
exists(%{$hash{a}{b}}, 'c')

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Dave.

In reply to Re^5: Looping through a hash reference is creating a key...? by dave_the_m
in thread Looping through a hash reference is creating a key...? by the_slycer

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