Instantiating a class with different types at runtime

[Marduk via Digitalmars-d-learn]

Dear all,

I would like to have a kind of template class like the following:
  class Example {

    this(Type_left x, Type_right y) {
      this.left = x;
      this.right = y;
    }

    Type_left left;
    Type_right right;

  }

Such that at runtime I can instantiate it with different types:

new Example(int a, int b);

new Example(int a, string b);

I have read about templates and abstract classes, but I have not 
figured how to get this to work. Thanks.