Typescript inheritance function not same as documentation

The specification mentions that the following function will be used for extension :

var __extends = this.__extends || function(d, b) {
    for (var p in b) if (b.hasOwnProperty(p)) d[p] = b[p];
    function f() { this.constructor = d; }
    f.prototype = b.prototype;
    d.prototype = new f();
}

However the function generated currently is :

var __extends = this.__extends || function (d, b) {
    function __() { this.constructor = d; }
    __.prototype = b.prototype;
    d.prototype = new __();
};

This breaks static inheritance:

class A{
    fooMem=10;
    static fooStat=10;
}
class B extends A{};

var b = new B();
alert(b.fooMem.toString());
alert(B.fooStat.toString());

Try It

Which would work if the documentation mentioned extends function is used : Test

Anybody know the reason why the documentation mentioned function was not used?