nl_tokens: Check if the given model may use the given id
pl_tokens: function ( model , id ) { var coll = this . getCollection ( model ) , duplicate = coll && coll . get ( id ) ; if ( duplicate && model !== duplicate ) { if ( Backbone . Relational . showWarnings && typeof console !== 'undefined' ) { console . warn ( 'Duplicate id! Old RelationalModel=%o, new RelationalModel=%o' , duplicate , model ) ; } throw new <mask> ( "Cannot instantiate more than one Backbone.RelationalModel with the same id per type!" ) ; } }