nl_tokens: ES6 20 . 1 . 3 . 2 Number . prototype . toExponential ( fractionDigits )
pl_tokens: function NumberToExponentialJS ( fractionDigits ) { var x = this ; if ( ! IS_NUMBER ( this ) ) { if ( ! IS_NUMBER_WRAPPER ( this ) ) { throw MakeTypeError ( kIncompatibleMethodReceiver , "Number.prototype.toExponential" , this ) ; } // Get the value of this number in case it's an object. x = % _ValueOf ( this ) ; } <mask> f = IS_UNDEFINED ( fractionDigits ) ? UNDEFINED : TO_INTEGER ( fractionDigits ) ; if ( NUMBER_IS_NAN ( x ) ) return "NaN" ; if ( x == INFINITY ) return "Infinity" ; if ( x == - INFINITY ) return "-Infinity" ; if ( IS_UNDEFINED ( f ) ) { f = - 1 ; // Signal for runtime function that f is not defined. } else if ( f < 0 || f > 20 ) { throw MakeRangeError ( kNumberFormatRange , "toExponential()" ) ; } return % NumberToExponential ( x , f ) ; }