while (my $a = shift @a) {

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This won't work if the array contains anything that is false in boolean context, like 0, '', or undef. You really need to explicitly check the array's length somehow.

If you're really intent on squeezing the assignment into the while loop, try: 

while ( (my $a, @a) = @a ) {

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This works because when evaluated in scalar context, the list assignment ( (list) = something ) returns the number of items in the right-hand side list. This little obscurity of syntax is probably one of the toughest to come to grips with, but it can be quite elegant at times.

In this case, I wouldn't actually use it since it reassigns most of @a to itself every time and is very inefficient in that respect.

blokhead

In reply to Re^2: Array Processing by blokhead
in thread Array Processing by Rajeshk

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