Backbone Collections - not able to set a 'rank' using set method

Question

In my backbone.marionette app, I am trying to set a model attribute 'rank' as it's loop index. here is the code of my collection:

 AngryCats = Backbone.Collection.extend({
          model:AngryCat,
          initialize: function(cats){
              var rank = 1;
              _.each(cats, function(cat){
                    cat.set('rank', rank);
                  rank++;
              })
          }
      });

But I am getting error as :

TypeError: cat.set is not a function
cat.set('rank', rank);

any one tell me what is wrong here? ( please check the fiddle link for complete coding )

Live Demo

Answer 1

You are passing array of javascript objects. But the set is only available in Backbone.Model instance. Only after initialisation, every single object converted into Backbone.Model Object.

You have to do like

 var rank = 1;
 _.each(cats, function(cat){
     cat.rank = rank;
     rank++;
  })