//// [genericPrototypeProperty.ts] class C { x: T; foo(x: T): T { return null; } } var r = C.prototype; // should be any var r2 = r.x var r3 = r.foo(null); //// [genericPrototypeProperty.js] var C = (function () { function C() { } C.prototype.foo = function (x) { return null; }; return C; })(); var r = C.prototype; // should be any var r2 = r.x; var r3 = r.foo(null);