This “mixin” concept uses the CRTP pattern, as mentioned in the post: https://en.wikipedia.org/wiki/Curiously_recurring_template_pattern https://en.wikipedia.or

This “mixin” concept uses the CRTP pattern, as mentioned in the post: https://en.wikipedia.org/wiki/Curiously_recurring_template_pattern https://en.wikipedia.org/wiki/Curiously_recurring_template_p... It actually does have specific applications. That Wikipedia article shows a good example of polymorphic method chaining. In a former life, I worked with Microsoft’s Active Template Library, which is entirely based on this pattern.