only if $h{x} (was a hash and) had at least one element

Then test whether the value of $h{x} actually is a hash reference.

If you say keys %{$h{x}} it is assumed you know what you are doing and want autovivifying, while dereferencing an undef value could just be a mistake. strict 'refs' catches that - that is what strict is about ;-)

By using keys you look inside the box (= the hashref), so perl autovivifies it, if it doesn't exist; by dereferencing you look at the box only.

--shmem 

_($_=" "x(1<<5)."?\n".q·/)Oo.  G°\        /
                              /\_¯/(q    /
----------------------------  \__(m.====·.(_("always off the crowd"))."·
");sub _{s./.($e="'Itrs `mnsgdq Gdbj O`qkdq")=~y/"-y/#-z/;$e.e && print}

In reply to Re^3: Keys() required to autovivify? by shmem
in thread Keys() required to autovivify? by jrw

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