To misquote Bill Clinton:

"It depends if your meaning of exist exists."

;)

Your table shows exactly a consistent behavior to exists when used with hashes. Unset values just don't exist.

$a[0] was never set, hence it doesn't exist.

I wasn't sure what you and sectokia meant with null-pointer, apparently it's the C-value of unset "gap" values¹ in the underlying C-array.

But those exist only on the C level, not logically in Perl.

> but there might be surprise cases (for (@a)? for ((), @a)? f(@a)?)

I don't understand, probably above my expertise.

Cheers Rolf
(addicted to the Perl Programming Language :)
see Wikisyntax for the Monastery

¹) with an index smaller than the maximal index of a set value

In reply to Re^4: Using exists to check element in array by LanX
in thread Using exists to check element in array by david

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