TypeScript mixins

mixins.ts

const MixinHello = <T extends new (...args: any[]) => A>(base: T) =>
    class extends base {
        hello() { }
    };

class A {
    a() { } 
}

class B extends A { 
    b() { }
}

class C extends MixinHello(B) {
    c() { }
}

let x = new C();
x.a();
x.b();
x.c();
x.hello();