I had to try this myself, because I couldn't believe it:

$a{undef} = 1;
print defined for keys %a;

# Output
1

# This doesn't work either:
%a = (undef, 1);

[download]

I wonder what he was thinking...

Ted Young

In reply to Re: undef as a key in a hash. by TedYoung
in thread undef as a key in a hash. by fenLisesi

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