nl_tokens: Node 0 . 10 - 0 . 12 does not supports Object . assign () Instead of modifying Object with polyfill we define private function object_assign ()
pl_tokens: function completeAssign ( target /*..sources*/ ) { for ( var index = 1 ; index < arguments . length ; index ++ ) { var source = arguments [ index ] ; //sources.forEach(source => { //let descriptors = Object.keys(source).reduce((descriptors, key) => { var descriptors = Object . <mask> ( source ) . reduce ( function ( descriptors , key ) { descriptors [ key ] = Object . getOwnPropertyDescriptor ( source , key ) ; return descriptors ; } , { } ) ; // by default, Object.assign copies enumerable Symbols too Object . getOwnPropertySymbols ( source ) . forEach ( function ( sym ) { var descriptor = Object . getOwnPropertyDescriptor ( source , sym ) ; if ( descriptor . enumerable ) { descriptors [ sym ] = descriptor ; } } ) ; Object . defineProperties ( target , descriptors ) ; //}); } return target ; }