code: function() {
          var me = this;
  
          me.length = 0;
          me.items = [];
          me.keys = [];
          me.map = {};
          me.indexMap = {};
  
          me.generation++;
          me.indexGeneration = me.generation;
          if (me.hasListeners.clear) {
              me.fireEvent('clear');
          }
      }
docs: Removes all items from the collection.  Fires the {@link #event-clear} event when complete.
  @since Ext 1