fatality (after a couple of warnings) for an empty input array

So don't do that :)

Test before entering the loop:

( my $i = $#a ) > 0 or die;
$b[ $i ] = $a[ $i ] + $a[ --$i ] while $i;

[download]

Never do in a loop, what can be done outside of it.

Wouldn't your version fail for an array with one element?

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
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". The enemy of (IT) success is complexity.
In the absence of evidence, opinion is indistinguishable from prejudice. Suck that fhit

In reply to Re^3: Abusing Map by BrowserUk
in thread Abusing Map by writch

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