I've taken advantage of short-circuiting operators to deal with this in the past, like so:
if (exists($x->{a}) && exists($x->{a}->{c}) { #do stuff }

Might get annoying if your hash is particularly deep, though.

In reply to Re: exists on hash autovivifies right? by menolly
in thread exists on hash autovivifies right? by Anonymous Monk

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