
1 Oct
2009
1 Oct
'09
2:11 a.m.
On Wed, Sep 30, 2009 at 03:43:12PM +0100, Andrew Coppin wrote:
Well, try this: Go ask a random person how you add up a list of numbers. Most of them will say something about adding the first two together, adding the third to that total, and so forth. In other words, the step by step instructions. Very few of them will answer that the sum of an empty list is defined to be zero, and the sum of a non-empty list is defined to be the first number plus the sum of the list tail.
Maybe they would say that you have to go adding each number to the others, i.e. they're thinking with a fold. -- Felipe.