I don't understand what you're saying. In the second example, %{$h{x}} is being autovivified by the use of keys() to create an empty hash at $h{x}. In the first example, the exact same expression, but without the call to keys(), is a syntax error.

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

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