I recommend looking at the khash implementation https://github.com/attractivechaos/klib/blob/master/khash.h https://github.com/attractivechaos/klib/blob/master/

I recommend looking at the khash implementation https://github.com/attractivechaos/klib/blob/master/khash.h https://github.com/attractivechaos/klib/blob/master/khash.h It's very competitive to optimized implementations like abseil and much, much better than the C++ STL one.