arrays don't have a concept of "(un)defined"
Yeah, that's an odd design decision which I personally disagree with. I see no logical reason to distinguish between "empty" and "undefined" for scalars, but not for arrays.

In any case, I considered going into that in my previous comment, but obviously decided against it. I probably should have, given that the literal answer to "How to differentiate an empty array from an uninitialized one?" is "You don't, because Perl doesn't." 

$ perl -wMstrict -MData::Dump -e 'dd split /-|(x)/, "-", -1'
("", undef, "")

[download]
Interesting. I wasn't aware of that behavior in split. Thanks for pointing it out!

In reply to Re^3: How to differentiate an empty array from an unitialized one? by dsheroh
in thread How to differentiate an empty array from an unitialized one? by iatros

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