To clarify - unlike scalars, arrays and hashes can't be "undefined". They can be empty, which is slightly different.

monarch, to test for emptiness, you said:

If the hash is empty then (@keyarr == 1).

I think you mean 0 not 1:

my %hash;
my @keyarr = keys %hash;
print scalar @keyarr;

[download]

prints 0.

s^^unp(;75N=&9I<V@`ack(u,^;s|\(.+\`|"$`$'\"$&\"\)"|ee;/m.+h/&&print$&

In reply to Re^2: Defined vs. undefined by muntfish
in thread Defined vs. undefined by tamaguchi

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