Well, actually my code could just be replaced with perl -e ''. But this is just my demo code to show the problem that I encountered.

My real code looked like: 

if (%{$h{x}}) { ... }

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by which I meant to execute the body of the if statement only if $h{x} (was a hash and) had at least one element. But instead I got a syntax error. I had to switch to 
if (keys %{$h{x}}) { ... }

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which was more than I wanted to say.

I was wondering why the use of keys() made perl smart enough to autovivify my hash, but the use of %{$h{x}} wasn't enough to cause it to autovivify (and then return a false value since the autovivified hash value was empty).

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

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