http://www.perlmonks.org?node_id=17420

I gave two ways to do it. There is no way to do it without some sort of loop happening somewhere. It is also why I said that that is the loopish way. Sorry if I gave too much information for your taste. I see your answer.. oh wait.. you didn't have an answer.

Cheers,
KM

• Comment on RE: RE: RE: RE: Answer: How can I add all the numbers in an array with out doing a foreach loop?

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RE: RE: RE: RE: RE: Answer: How can I add all the numbers in an array with out doing a foreach loop?
by Adam (Vicar) on Jun 10, 2000 at 00:46 UTC
Its unfortunate, KM, that you didn't really read the question, or my posts for that matter. You might have noticed that I was not putting you down or saying that your answer sucked. I was merely pointing out that you gave an answer that ignored the question, followed by one that didn't. As for why I hadn't posted my own answer? Thats because I liked your second answer. But you want one from me that doesn't use a loop? Ok. I'll use recursion then:
sub addArray{ shift(@_) + addArray(@_) if(@_) } \$total = addArray( 1, 3, 8, 15, 7, 5, 3 )

Update: Two other things KM, I notice that you voted -- on my original comment. I'm not sure why. Nothing I said in that post was incorrect or rude. I also have noticed that my recursive answer is similar to the one that Btrott posted. I'm not sure why I should care, but I didn't want you to think I had copied it, as I had not read it when I first posted this. Cheers.

Recursion is a looping construct as well. As everybody keeps pointing out there isn't really a way to do this without some kind of loop going on somewhere.

Nuance

Sorry Nuance, Recursion is NOT a loop.
Recursion works by building up the stack, delaying evaluation until the end. A loop evaluates as it goes. There is a big difference between the two.

Think about it this way: The recursive method that I posted says to add the first number to the sum of the other numbers. That can't be done until the sum of the other numbers is known, so it puts the number on the stack and trys to sum the other numbers by the same method. It does this, pushing the list onto a stack, until there is only one number left, then it sums the stack. This is not a loop. Its not even close.