Supporting polymorphic collections

[dnsco]

Howdy!

Right now backbone seems to only support collections of one type, we're working on a stream with many polymorphic types that all quack the same.

It'd be nice to implement this via inheritance(extend), rather than our current technique of creating proxies/mixins in the base class.

backbone collection seems to have a hardcoded new this.model in it,

I was thinking about doing something like:

modelClass : function(){
   return  this[postType]
}

this.model = this.model || this.modelClass()

new this.model

is this a change you would like to have implemented, or are you opposed to it for an ideological reason?

If you want it, I'll implemented, as it will help me on a couple projects I'm working on.

[jashkenas]

Fortunately, because of the (in my opinion, buggy) way that JavaScript constructors work, you can already do collections with polymorphic models. Like so:

var Library = Backbone.Collection.extend({

  model: function(attrs, options) {
    if (condition) {
      return new PublicDocument(attrs, options); 
    } else {
      return new PrivateDocument(attrs, options);
    }
  }

});

[dnsco]

Thanks dude, I wrote this issue when I was working on a client project, but now Imma integrate it into diaspora and it will be better <3333333