Actually, the docs say: 
    undef $ref;
    if (exists $ref->{"Some key"})    { }
    print $ref;         # prints HASH(0x80d3d5c)

[download]
"This surprising autovivification in what does not at first--or even second--glance appear to be an lvalue context may be fixed in a future release."

Translating 'autovivication' from the ancient Latin I get: "of bringing itself to life," so I take it to mean "self-define" in the context.

As for a workaround, I would expect using 'defined()' instead of 'exists()' ought to do it.

-M

Free your mind

In reply to Re: Unexpected exists() behavior by Moron
in thread Unexpected exists() behavior by tsmoyers

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