nl_tokens: Returns a fresh property descriptor that is guaranteed to be complete ( i . e . contain all the standard attributes ) . Additionally any non - standard enumerable properties of attributes are copied over to the fresh descriptor .
pl_tokens: function normalizeAndCompletePropertyDescriptor ( attributes ) { if ( attributes === undefined ) { return undefined ; } var desc = toCompletePropertyDescriptor ( attributes ) ; // Note: no need to call FromPropertyDescriptor(desc), as we represent // "internal" property descriptors as proper Objects from the start for ( var name in attributes ) { if ( ! isStandardAttribute ( <mask> ) ) { Object . defineProperty ( desc , name , { value : attributes [ name ] , writable : true , enumerable : true , configurable : true } ) ; } } return desc ; }