function( model ) {
			var coll = this.getCollection( model );

			if ( coll ) {
				var modelColl = model.collection;
				coll.add( model );
				this.listenTo( model, 'destroy', this.unregister, this );
				this.listenTo( model, 'relational:unregister', this.unregister, this );
				model.collection = modelColl;
			}
		}
function( model ) {
			var coll = this.getCollection( model );

			if ( coll ) {
				var modelColl = model.collection;
				coll.add( model );
				this.listenTo( model, 'destroy', this.unregister, this );
				this.listenTo( model, 'relational:unregister', this.unregister, this );
				model.collection = modelColl;
			}
		}
function ( model ) { var coll = this . getCollection ( model ) ; if ( coll ) { var modelColl = model . collection ; coll . add ( model ) ; this . listenTo ( model , 'destroy' , this . unregister , this ) ; this . listenTo ( model , 'relational:unregister' , this . unregister , this ) ; model . collection = modelColl ; } }
Add a 'model' to its appropriate collection. Retain the original contents of 'model.collection'.
@param {Backbone.RelationalModel} model
Add a model to its appropriate collection . Retain the original contents of model . collection .