Thanks! I think this is the answer I was looking for. Keys() is supplying some extra magic to cause autovivification whereas plain scalar context unfortunately doesn't. Oh well. Unfortunately, I bet on if (%{$h{x}}) autovivifying because I knew if (keys %{$h{x}}) did.

In reply to Re^2: Keys() required to autovivify? by jrw
in thread Keys() required to autovivify? by jrw

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