It's actually more surprising that the person who can write this otherwise clean and modern C++17 code produce this awful abomination. The only possible explan

It's actually more surprising that the person who can write this otherwise clean and modern C++17 code produce this awful abomination. The only possible explanation is, he literally port the existing code written in a very dynamic language by hand. He is not stupid, far from it. It's just he also ported the dynamic part of the code so well.