All of that #define madness replace with templates and constexpr. I would also add if you can get it running on more than one compiler. G++ and MSvc and clang

All of that #define madness replace with templates and constexpr. I would also add if you can get it running on more than one compiler. G++ and MSvc and clang. Each one has its own subtle bits of errors it likes to throw out. Also get it running properly with something like valgrind. You are going to need it.