//// [superWithGenericSpecialization.ts] class C { x: T; } class D extends C { y: T; constructor() { super(); // uses the type parameter type of the base class, ie string } } var d: D; var r: string = d.x; var r2: number = d.y; //// [superWithGenericSpecialization.js] var __extends = (this && this.__extends) || function (d, b) { for (var p in b) if (b.hasOwnProperty(p)) d[p] = b[p]; function __() { this.constructor = d; } d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __()); }; var C = (function () { function C() { } return C; })(); var D = (function (_super) { __extends(D, _super); function D() { _super.call(this); // uses the type parameter type of the base class, ie string } return D; })(C); var d; var r = d.x; var r2 = d.y;