Passing class as parametr with generics

Here is live example(Sorry, had to use url shortener, link characters break markup) TypeScript version 1.6.2

I have two services across my angular2 application. Let's name them ServiceA and ServiceB. Each one of them, have similar data structure, so I decided to use extends to not write same code twice. The class which will provide data structure is called Pages and looks like this:

class Pages {
public pages = [];
private active: number = 0;

get current() {
return this.pages[this.active];
}

constructor(private page, public name: string) { }

changeActive(page: number): void {
this.active = page;
}

addPage(): void {
this.pages.push(
new this.page(this.name + (this.pages.length + 1))
);
}
}


pages array will contains class instances unique for each service. Here is an example of one for ServiceA:

// ServiceA.pages will be filled with instanced of this class.
// ServiceB.pages will use different class but the constructor
// will be simmilar(will take only one argument name: string)
class PageA {
public uniquePropertyA: string = 'Hello World!';
constructor(public name: string) { }
// unique methods of PageA
}


Services will look quite similar. Here preview of ServiceA:

class ServiceA extends Pages {
constructor() {
super(PageA, 'ServiceA #');
}
}

// demo
var sA = new ServiceA();
sA.addPage();
sA.current. // Hey there is no auto complete!


This example works fine, however I do not get autocomplete each page because its type is any. I was trying to use "generics" to make it work, sadly with no success but here it is. Basicly I want to know which constructor I passed to Pages class, so I can get right types.

I hope you guys can help me with this one.

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