populating a collection from a json file

I want to populate a collection from an json file, which has other data apart from the array of data items. I came to know that parse function on collection should be used to return the array of data items, but my collection is not getting populated from the json file. When i kept a breakpoint at parse method in firebug, the control is not at all coming there.

This is my code

        var m1 = Backbone.Model.extend({                
                title:'Title1',
                tag:'html',
                date: 'Today'
        })
        cll = Backbone.Collection.extend({
            url:'/combodata.json?uu',
            model:m1,
            parse:function(res){                    
                return res.items;
            }
        });

        ci = new cll();
        ci.fetch();

The json response will be like this

{
'identifier': 'title',
items:[
    {title:'A', tag:"htmlcss", date:'today'},
    {title:'AA', tag:"htmlcss", date:'today'},
    {titl开发者_如何转开发e:'B', tag:"htmlcss", date:'today'},
    {title:'C', tag:"htmlcss1", date:'today'}
]}

Please point me where I'm wrong.

Not an expert at JSON but I tried to validate your JSON at jsonlint.com. It fails at line 2

Parse error on line 1:
{    'identifier': 'title
-----^
Expecting 'STRING', '}'

Kindly verify if your JSON is valid or not.

Just checked another site for your JSON validation http://jsonformatter.curiousconcept.com/ and it seems, that string identifiers should be used with double quotes instead of single quotes. Replacing your single quotes with double quotes might help.