void Ex01()
        {
            When("an extension is added to the AvaloniaController", () => AvaloniaController.AddExtension(Extension));
            When("the AvaloniaController is enabled for the element", () => AvaloniaController.SetIsEnabled(Element, true));

            When("the element is attached to the logical tree", () => Element.AttachToLogicalTree());
            Then("the extension should be attached", () => Extension.Attached);

            When("the element is detached from the logical tree", () => Element.DetachFromLogicalTree());
            Then("the extension should be detached", () => Extension.Detached);
        }
 void Ex02()
 {
     When("an extension is added to the AvaloniaController", () => AvaloniaController.AddExtension(Extension));
     Then("the container of the extension should be retrieved", () => AvaloniaController.Retrieve <TestExtension, object>(Controller) == TestExtension.TestExtensionContainer);
 }