The fact is that your x= tricks works is just as much as the undef() because of undocumented behaviour.
No, the behavior of assignment and the x operator are defined for array slices. If you don't like the zero, one works just as well.

That said, I like the ref trick. It's fast, documented, and not too bizarre. ++

I've thought about it a little more, and I wonder whether it actually is documented behavior. Is \ documented for array slices? Dumper tells me it's behaving like \(), making a list of references, which is sensible. I guess a slice is a list, even without surrounding parentheses...

Caution: Contents may have been coded under pressure.

In reply to Re^6: Adding Unique Elements to Array by Roy Johnson
in thread Adding Unique Elements to Array by thekestrel

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