On Fri, Aug 24, 2012 at 7:54 PM, Ole Friis Østergaard
<olef...@gmail.com> wrote:
> Oh, I found out that it's been attempted before, but with same result:
> https://groups.google.com/forum/#!searchin/angular/chunk/angular/F0kNH69YqL0/mmENSj8dR1MJ

On Sat, Aug 25, 2012 at 3:30 PM, Godmar Back <god...@gmail.com> wrote:
>
> I had completely put you on the core team, Pawel, with your helpful and
> insightful comments.

> Who is on the core team, though?

> Does the core team read this list?  In the
> short time I've joined, I've seen numerous questions repeated over and over,
> which arise mainly due to the low quality (or total lack) of documentation.

> Perhaps a core team member could subscribe to the list, and whenever a
> frequent question arises, update the documentation?

Here is the working jsFiddle:

Hi Pawel

Thanks for your solution! Meanwhile I found my own working solution, in which I simply set $$hashKey of a chunk to the index of that chunk. That works just as well, though it has a potential problem, which I believe your solution has as well: ng-repeat will consider two chunks the same even if they contain different values. In my solution this happens all the time, since the first chunk always gets $$hashKey 0, etc. In your solution, it happens when the string representation of different chunks are incidentally the same - or for the chunks [12, 3, 4] and [1, 23, 4], for example. However, this doesn't really matter in practice, since the output of the "chunk" filter will typically be used for a later ng-repeat, and the differences will be caught there.

I guess your implementation is the most elegant. I'll insert mine at the end of this post. I've refactored out some functions to make it more readable, which of course makes it more verbose.

Both solutions have the major problem that they are bound to the internal workings of Angular... but I guess it's the best we can do.

Thank you so much for your time, Pawel. Everybody now has a working "chunk" filter, so that using Twitter Bootstrap with Angular is not a dark art anymore. I hope the Angular developers will create an official, clean "chunk" filter sometime in the future.

myApp.filter('chunk', function() {

  function chunkArray(array, chunkSize) {

    var result = [];

    var currentChunk = [];

    for (var i=0; i<array.length; i++) {

      currentChunk.push(array[i]);

      if (currentChunk.length == chunkSize) {

        result.push(currentChunk);

        currentChunk = [];

      }

    }

    if (currentChunk.length > 0) {

      result.push(currentChunk);

    }

    return result;

  }

  function defineHashKeys(array) {

    for (var i=0; i<array.length; i++) {

      array[i].$$hashKey = i;

    }

  }

  return function(array, chunkSize) {

    if (!(array instanceof Array)) return array;

    if (!chunkSize) return array;

    var result = chunkArray(array, chunkSize);

    defineHashKeys(result);

    return result;

  }

});