fmt
Formatting library as an alternative to C stdio and C++ iostreams
... or at compile time. The library produces compact per-call compiled code. The library is highly portable and relies only on a small set of C++11 features, like variadic templates, type traits, rvalue references, decltype, trailing return, types, deleted functions, alias templates. These are available in GCC 4.8, Clang 3.0, MSVC 19.0 (2015) and more recent compiler version. For older compilers use {fmt} version 4.x which is maintained and only requires C++98.