The point was that 
while( my $next = $iter->() ) {
    ($next) = @$next;
    ...
}

is a complicated version of 
while( my $next = @{ $iter->() } ) {
    ...
}

[download]

Not so. In the latter case when the iterator returns undef to terminate iteration, you will attempt to dereference that undef causing an error.

In the former, the loop terminates and the dereference is never reached.

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re^7: Dumb, non-question: How to return 'nothing'. by BrowserUk
in thread Dumb, non-question: How to return 'nothing'. by BrowserUk

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