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 var funProto = Function.prototype;

 assertEq(Object.getOwnPropertyDescriptor(funProto, "prototype"), undefined);

 function Point(x, y) { this.x = x; this.y = y; }

 var YAxisPoint = Point.bind(null, 0);

 assertEq(YAxisPoint.prototype, undefined);

 var oldPoint;

 for (var i = 0, sz = 9; i < sz; oldPoint = point, i++)

 {

   var point = new YAxisPoint(5);

   assertEq(point === oldPoint, false);

   assertEq(point.x, 0);

   assertEq(point.y, 5);

   assertEq(Object.getOwnPropertyDescriptor(funProto, "prototype"), undefined);

   assertEq(Object.getOwnPropertyDescriptor(YAxisPoint, "prototype"), undefined);

 }