#each iteration number in Ember.js or {{#index}} - ember.js

Question

According to this question, it was possible to do something like this with Handlebars rc1:
{{#each links}}
<li>{{#index}} - {{url}}</li>
{{/each}}
{{#index}} would basically give you the iteration index, which is really useful when creating tables.
When I try this with Ember.js rc3, I get an unexpected token error. Does this not work anymore? Did it ever work? Is there another way to get the iteration index?

Answer 1

It looks like it was possible. Can't get it to work with HBS RC3. Probably, is deprecated.
Here's a "hand written" HBS helper.

Answer 2

This can help you gettin the index with {{index}} and side by side you can know if the iteration in on first or last object of the Array with {{first}} and {{last}} respectively.
Ember.Handlebars.registerHelper("foreach", function(path, options) {
var ctx;
var helperName = 'foreach';
if (arguments.length === 4) {
Ember.assert("If you pass more than one argument to the foreach helper, it must be in the form #foreach foo in bar", arguments[1] === "in");
var keywordName = arguments[0];
options = arguments[3];
path = arguments[2];
helperName += ' ' + keywordName + ' in ' + path;
if (path === '') {
path = "this";
}
options.hash.keyword = keywordName;
} else if (arguments.length === 1) {
options = path;
path = 'this';
} else {
helperName += ' ' + path;
}
options.hash.dataSourceBinding = path;
// Set up emptyView as a metamorph with no tag
//options.hash.emptyViewClass = Ember._MetamorphView;
// can't rely on this default behavior when use strict
ctx = this || window;
var len = options.contexts[0][path].length;
options.helperName = options.helperName || helperName;
options.contexts[0][path].map(function(item, index) {
item.index = index;
item.first = index === 0;
item.last = index === len - 1;
})
if (options.data.insideGroup && !options.hash.groupedRows && !options.hash.itemViewClass) {
new GroupedEach(ctx, path, options).render();
} else {
return Ember.Handlebars.helpers.collection.call(ctx, Ember.Handlebars.EachView, options);
}
});
and this can be tested like
{{#foreach array}}
{{log index first last}}
{{/foreach}}

Answer 3

i had the same problem recently i finish by writing a bound helper and passing them objects via Binding for example item here is an ember DS.Store object and content is a 'content' of the controller. hope it
Ember.Handlebars.registerBoundHelper 'isPair', (content, options)->
item = options.hash.item
content_name = options.hash.content || 'content'
if #get(content_name).indexOf(item) % 2 == 0 then 'is-pair' else 'is-unpair'
and in you view you call it
{{isPair content itemBinding='order'}}
i don't know if it is what you looking for but it might give you some ideas how to use it in your project.
btw. Ember overwrites #each helper that's why there it no #index i suppose