enum to string in modern C++11 / C++14 / C++17 and future C++20

Question

Contrary to all other similar questions, this question is about using the new C++ features.

• 2008 c Is there a simple way to convert C++ enum to string?
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Answer 1

Magic Enum header-only library provides static reflection for enums (to string, from string, iteration) for C++17.

#include 

enum Color { RED = 2, BLUE = 4, GREEN = 8 };

Color color = Color::RED;
auto color_name = magic_enum::enum_name(color);
// color_name -> "RED"

std::string color_name{"GREEN"};
auto color = magic_enum::enum_cast(color_name)
if (color.has_value()) {
  // color.value() -> Color::GREEN
};

For more examples check home repository https://github.com/Neargye/magic_enum.

Where is the drawback?

This library uses a compiler-specific hack (based on __PRETTY_FUNCTION__ / __FUNCSIG__), which works on Clang >= 5, MSVC >= 15.3 and GCC >= 9.

Enum value must be in range [MAGIC_ENUM_RANGE_MIN, MAGIC_ENUM_RANGE_MAX].

• By default MAGIC_ENUM_RANGE_MIN = -128, MAGIC_ENUM_RANGE_MAX = 128.

• If need another range for all enum types by default, redefine the macro MAGIC_ENUM_RANGE_MIN and MAGIC_ENUM_RANGE_MAX.

• MAGIC_ENUM_RANGE_MIN must be less or equals than 0 and must be greater than INT16_MIN.

• MAGIC_ENUM_RANGE_MAX must be greater than 0 and must be less than INT16_MAX.

• If need another range for specific enum type, add specialization enum_range for necessary enum type.

  #include 
  
  enum number { one = 100, two = 200, three = 300 };
  
  namespace magic_enum {
  template <>
    struct enum_range {
      static constexpr int min = 100;
      static constexpr int max = 300;
  };
  }