Why are you looping over array, when you are checking over the bounds of args? Shouldn't it be
s += args[i];
Normally, you loop over the thing you're checking the bounds for.
The fact that this has been sitting on HN front page all day and there's no single, satisfactory answer (I mean, is this a satisfactory answer?) is to me a Key Failure of the for loop. For loops just don't capture very much in terms of semantics.
Why are we befuddled by what this piece of code does? You can get into stupid pedantry about what a closure is (yes, looking at the top comment here), and various other details, but that misses the point of the article, which is that for-loop are practically an anti-pattern.
As a community, we've long realized that functions like fold, filter and map are good things, better than our equivalent of the for-loop, which is recursing over the data-structure. You better have a solid reason to write your own pattern match over a list. In all my years of writing functional code, I've only once had to write a function that recursed over a list, and boy was it a regrettable function.
I see the comments here which argue about what a closure really is (and there is a lot of conflicting info out there. Even Douglas Crockford explains it differently than the comments I've seen on this article) when the point of the article is that for loop are an anti-pattern - exactly as you say.
This realization really hit home for me when I started using Clojure and kept trying to figure out how to do a for-loop. Once you wrap your head around map, reduce and filter, all of a sudden you realize how expressive a programming language really can be.
Normally, you loop over the thing you're checking the bounds for.
The fact that this has been sitting on HN front page all day and there's no single, satisfactory answer (I mean, is this a satisfactory answer?) is to me a Key Failure of the for loop. For loops just don't capture very much in terms of semantics.
Why are we befuddled by what this piece of code does? You can get into stupid pedantry about what a closure is (yes, looking at the top comment here), and various other details, but that misses the point of the article, which is that for-loop are practically an anti-pattern.
As a community, we've long realized that functions like fold, filter and map are good things, better than our equivalent of the for-loop, which is recursing over the data-structure. You better have a solid reason to write your own pattern match over a list. In all my years of writing functional code, I've only once had to write a function that recursed over a list, and boy was it a regrettable function.