This repository contains a header-only constexpr multimap under 'KonstxprMultiMap/KonstxprMultiMap.hpp'.
For some toy examples look at 'KonstxprMultiMap/KonstxprMultiMapTests.cpp'.
The generic constexpr multimap can be used for fast compile time retrievals.
Under the hood the multimap is implemented as a std::array of std::pair<Key, Value> where Key and Value are template parameters.