http://ajaxian.com/archives/the-future-of-javascript-an-update-from-brendan-eich

I’m a big fan of JavaScript….

/not into platform religious wars, use whatever makes you productive.

Heh, I knew someone would point that out… You’re correct, of course. It’s just that sometimes I prefer to be approximately right, rather than exactly wrong.

Actually thats not quite right. Enumerable is a module/mixin that is imported into certain classes. Theres a difference.

Array.prototype.reduce=function(func) {
var l=this.length;
var s=”;
for (var i=0;i

Thanks for the pointer! I was interested, of course, and I’m quite impressed with Sam’s implementation of Enumerable, it’s elegant and complete. I guess this is the passage that explains the Prototype-way to handle the collections I was mentioning:

The $A() function converts the single argument it receives into an Array object.. One suggested use is to convert DOM NodeLists into regular arrays, which can be traversed more efficiently.

This is all great, and I’ll be using $A() a lot, but I wonder why Prototype doesn’t include the Enumerable methods inside such collections by default (as it does for Arrays)…

(Oh, and a little bug report: you can’t see a blockquote’s text in the Live Preview, it’s the same color as the background.)

Yes, you could have a ruby-esque each in JS by making each a method of class Array. The problem with that approach is that there are other important collection of objects one would also like to traverse with each. For instance, a childNodes returns a NodeList object in Firefox (and who knows what in IE), and document.getElementsByTagName returns objects of a class I haven’t been able to ascertain (theoretically it should be a NodeList object too but that’s false).

You could try to solve this, somewhat rough-handedly, by making each a method of class Object, but while that will work in Firefox it won’t in IE.

Ruby solves this problem by having an Enumerable class of which every collection class is a children, but to my knowledge there’s nothing like that in JS right now.

And that’s why I prefer to have each as a top-level method, as I described in a previous comment.


Array.prototype.each = function(f) {
for (var i = 0; i