How to convert an enum to a string in modern C++

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After reading many answers, I did not yet find any:

• Elegant way using C++11, C++14 or C++17 new features

• Or something ready-to-use in Boost

• Else something planned for C++20

Example

An example is often better than a long explanation.

You can compile and run this snippet on Coliru.

(Another former example is also available)

#include 
#include 

struct MyClass
{
    enum class MyEnum : char {
        AAA = -8,
        BBB = '8',
        CCC = AAA + BBB
    };
};

// Replace magic() by some faster compile-time generated code
// (you're allowed to replace the return type with std::string
// if that's easier for you)
const char* magic (MyClass::MyEnum e)
{
    const std::map MyEnumStrings {
        { MyClass::MyEnum::AAA, "MyClass::MyEnum::AAA" },
        { MyClass::MyEnum::BBB, "MyClass::MyEnum::BBB" },
        { MyClass::MyEnum::CCC, "MyClass::MyEnum::CCC" }
    };
    auto   it  = MyEnumStrings.find(e);
    return it == MyEnumStrings.end() ? "Out of range" : it->second;
}

int main()
{
   std::cout << magic(MyClass::MyEnum::AAA) <<'\n';
   std::cout << magic(MyClass::MyEnum::BBB) <<'\n';
   std::cout << magic(MyClass::MyEnum::CCC) <<'\n';
}

Constraints

• Please no valueless duplication of other answers or basic link.

• Please avoid bloat macro

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

(Disclosure: I'm the author of the library.)
#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;
};
}


Stack Overflow Q#28828957, score: 138