Changed to collectionOptions and accepts an options hash or a function

README.md

@@ -171,11 +171,12 @@ By default, the relation's `key` attribute will be used to create a reference to
 If you set `collectionKey` to a string, it will use that string as the reference to the RelationalModel, rather than the relation's `key` attribute.
 If you don't want this behavior at all, set `collectionKey` to false (or any falsy value) and this reference will not be created.
 
-### collectionOptionCallback
+### collectionOptions
 
-Value: a function that accepts an instance of a `Backbone.RelationalModed` and returns an option hash
+Value: an options hash or a function that accepts an instance of a `Backbone.RelationalModed` and returns an option hash
 
-If supplied, this function should return an option hash that will be used when initializing the collection at the other end of a ToMany-relation. The function will be called with the initialized instance from the first end of the relation as the only argument
+Used to provide options for the initialization of the collection in the "Many"-end of a `HasMany` relation. Can be an options hash or
+a function that should take the instance in the "One"-end of the "HasMany" relation and return an options hash
 
 ### includeInJSON
 

backbone-relational.js

@@ -653,7 +653,7 @@
 			reverseRelation: { type: 'HasOne' },
 			collectionType: Backbone.Collection,
 			collectionKey: true,
-			collectionOptionsCallback: function( instance ){ return {} }
+			collectionOptions: {}
 		},
 
 		initialize: function() {
@@ -668,8 +668,11 @@
 			if ( !this.collectionType.prototype instanceof Backbone.Collection.prototype.constructor ){
 				throw new Error( 'collectionType must inherit from Backbone.Collection' );
 			}
-
-			this.setRelated( this.prepareCollection( new this.collectionType( [], this.options.collectionOptionsCallback( this.instance ) ) ) );
+
+			var collectionOptions = _.isFunction( self.options.collectionOptions ) ?
+					self.options.collectionOptions( this.instance ) :
+					self.options.collectionOptions;
+			this.setRelated( this.prepareCollection( new this.collectionType( [], collectionOptions ) ) );
 			this.findRelated( { silent: true } );
 		},