> and only works if undef is not a possible value

If you are suffering from the undef is a value problem¹, than call iterators in list context. Re: list context (iterators).

I have to admit that I didn't try to understand your code , though! :)

Cheers Rolf

PS: Je suis Charlie!

¹) aka "0 but true" nonsense

In reply to Re^2: An iterator for (not "iterating") a recursive data structure. by LanX
in thread An iterator for (not "iterating") a recursive data structure. by BrowserUk

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