I suspect you haven't tested this. It might seem reasonable to assume that shift on an empty array returns an empty list. However, my testing on Perl 5.8.8 and 5.10 shows that shift @empty returns a single undef, not an empty list and your example produces an endless loop.

- tye        

In reply to Re^3: Unshift and push inside of map operation. (test) by tye
in thread Unshift and push inside of map operation. by LNEDAD

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