First, to clarify, the answer I posted for gdig321 was not intended to represent the only Way to do it (see TMTOWTDI). I'm just used to using the -> operator.

The two examples you gave are slightly different. First:
$evilhash->{1} = {}
makes $evilhash a reference to an anonymous hash. The anonymous hash has one key, "1", with an empty hashref as the value corresponding with this key.
$evilhash{1} = {}
makes %evilhash, a true hash, which has one key, "1", with an empty hashref as the value corresponding with this key.

Your two examples are correctly written and will produce the same result, I agree. Thanks for the clarification,

-Adam