This is definitely subjective, and a point for documentation. In both cases, $os->name is trying to communicate that the $os object has no name. It's actually more consistent with this interpretation in my mind to return an undef here, since an undef feels more like a null to me, as opposed to an empty string. But either is acceptable so long as it's documented that way.

Assuming you are dealing with 5.10.0 or later (I think), the Logical Defined Or actually gives a very elegant way of writing your case, and makes undef a preferred choice: 

printf "Operating System: %s\n", $os->name( long => 1 ) // 'undef';

[download]
or even 
printf "Operating System: %s\n", $os->name( long => 1 ) // (`uname -o 
+-r` =~ s/\n//r);

[download]

#11929 First ask yourself `How would I do this without a computer?' Then have the computer do it the same way.

In reply to Re: A question about method return values and error checking by kennethk
in thread A question about method return values and error checking by wee

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