reflection
haskellのreflection
Functional pearl: implicit configurations--or, type classes reflect the values of types
https://qiita.com/mod_poppo/items/50ad2c0ee66171cc1ee9
https://www.tweag.io/blog/2017-12-21-reflection-tutorial/
https://viercc.github.io/blog/posts/2018-12-18-reflection-trick.html