Ext Core comp with ExtJS

[ci11111]

Im new to Ext Core, and just seen the combo and carousels that are really nice
Is it a good idea to include both extjs and extcore scripts, to combine Core features with extjs grids, stores... and layouts? (possible incompatibilities or heaviness for browsers)
thanks

[mitchellsimoens]

Ext Core is just the core of Ext JS and has not widgets. Ext JS 3's core is different than Ext JS 4. Ext JS 4's core is the core of the framework (basically ext.js and ext-debug.js but without a couple things)

[basememara]

If I wanted to use the class system only, do I just link ext.js or does it have other dependencies?

My scenario is that I have an existing website that is mostly built in jQuery and pure Javascript objects like this:

MyNamespace.MyObject = {
  prop1: 'abc',
  prop2: '123',
  initSearch: function () {
        $('#search-container input[type=submit]').click(function () {
            var query = $('#search-container input[type=text]').val();
            this.applyFilter(query);
        });
  },
  applyFilter: function (query) {
    //do something
  }
}

I want to replace the above object with the Sencha class system and need the core instead of the whole Ext JS. Is this possible?