Hi folks,

I would like to propose a generic library for compile-time routing.

`if constexpr` and "SFINAE/Concepts based class/function template specialization" are generally used for compile-time routing in complex template libraries. However, according to my experience, they are not so easy to code, maintain or test. Therefore, I designed a template library specifically for compile-time routing with more usability, enabling template library based on this library to have more extendibility and testability.

Please find the draft of the proposal here: https://raw.githubusercontent.com/wmx16835/my-stl/4889927d02056acd29f7f98afdbb87423878e970/doc/applicable_template_preview.pdf

I am looking forward to your valuable comments.

Thanks,
Mingxin Wang