 __  __             _        ______                          _____
|  \/  |           (_)      |  ____|                        / ____|_     _
| \  / | __ _  __ _ _  ___  | |__   _ __  _   _ _ __ ___   | |   _| |_ _| |_
| |\/| |/ _` |/ _` | |/ __| |  __| | '_ \| | | | '_ ` _ \  | |  |_   _|_   _|
| |  | | (_| | (_| | | (__  | |____| | | | |_| | | | | | | | |____|_|   |_|
|_|  |_|\__,_|\__, |_|\___| |______|_| |_|\__,_|_| |_| |_|  \_____|
               __/ |
              |___/

Magic Enum C++

Header-only C++17 library provides static reflection for enums, work with any enum type without any macro or boilerplate code.

enum_cast obtains enum value from string or integer.
enum_value returns enum value at specified index.
enum_values obtains enum value sequence.
enum_count returns number of enum values.
enum_integer obtains integer value from enum value.
enum_name returns name from enum value.
enum_names obtains string enum name sequence.
enum_entries obtains pair (value enum, string enum name) sequence.
enum_index obtains index in enum value sequence from enum value.
enum_contains checks whether enum contains enumerator with such value.
enum_type_name returns name of enum type.
is_unscoped_enum checks whether type is an Unscoped enumeration.
is_scoped_enum checks whether type is an Scoped enumeration.
underlying_type improved UB-free "SFINAE-friendly" std::underlying_type.
ostream_operators ostream operators for enums.
bitwise_operators bitwise operators for enums.

Documentation

Features

C++17
Header-only
Dependency-free
Compile-time
Enum to string
String to enum
Iterating over enum

Examples

// For example color enum.
enum class Color { RED = 2, BLUE = 4, GREEN = 8 };

Enum value to string

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

String to enum value

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

Integer to enum value

int color_integer = 2;
auto color = magic_enum::enum_cast<Color>(color_integer);
if (color.has_value()) {
  // color.value() -> Color::RED
}

Indexed access to enum value

std::size_t i = 1;
Color color = magic_enum::enum_value<Color>(i);
// color -> Color::BLUE

Enum value sequence

constexpr auto& colors = magic_enum::enum_values<Color>();
// colors -> {Color::RED, Color::BLUE, Color::GREEN}
// colors[0] -> Color::RED

Number of enum elements

constexpr std::size_t color_count = magic_enum::enum_count<Color>();
// color_count -> 3

Enum value to integer

Color color = Color::RED;
auto color_integer = magic_enum::enum_integer(color);
// color -> 2

Enum names sequence

constexpr auto& color_names = magic_enum::enum_names<Color>();
// color_names -> {"RED", "BLUE", "GREEN"}
// color_names[0] -> "RED"

Enum entries sequence

constexpr auto& color_entries = magic_enum::enum_entries<Color>();
// color_entries -> {{Color::RED, "RED"}, {Color::BLUE, "BLUE"}, {Color::GREEN, "GREEN"}}
// color_entries[0].first -> Color::RED
// color_entries[0].second -> "RED"

Ostream operator for enum

using namespace magic_enum::ostream_operators; // out-of-the-box ostream operators for enums.
Color color = Color::BLUE;
std::cout << color << std::endl; // "BLUE"

Bitwise operator for enum

enum class Flags { A = 1 << 0, B = 1 << 1, C = 1 << 2, D = 1 << 3 };
using namespace magic_enum::bitwise_operators; // out-of-the-box bitwise operators for enums.
// Support operators: ~, |, &, ^, |=, &=, ^=.
Flags flags = Flags::A | Flags::B & ~Flags::C;

Checks whether type is an Unscoped enumeration.

enum color { red, green, blue };
enum class direction { left, right };

magic_enum::is_unscoped_enum<color>::value -> true
magic_enum::is_unscoped_enum<direction>::value -> false
magic_enum::is_unscoped_enum<int>::value -> false

// Helper variable template.
magic_enum::is_unscoped_enum_v<color> -> true

Checks whether type is an Scoped enumeration.

enum color { red, green, blue };
enum class direction { left, right };

magic_enum::is_scoped_enum<color>::value -> false
magic_enum::is_scoped_enum<direction>::value -> true
magic_enum::is_scoped_enum<int>::value -> false

// Helper variable template.
magic_enum::is_scoped_enum_v<direction> -> true

Static storage enum variable to string This version is much lighter on the compile times and is not restricted to the enum_range limitation.
```
constexpr Color color = Color::BLUE;
constexpr auto color_name = magic_enum::enum_name<color>();
// color_name -> "BLUE"
```

Remarks

magic_enum does not pretend to be a silver bullet for reflection for enums, it was originally designed for small enum.
Before use, read the limitations of functionality.
For the small enum use the API from the namespace magic_enum, and for enum-flags use the API from the namespace magic_enum::flags.

Integration

You should add the required file magic_enum.hpp.
If you are using vcpkg on your project for external dependencies, then you can use the magic-enum package.
If you are using Conan to manage your dependencies, merely add magic_enum/x.y.z to your conan's requires, where x.y.z is the release version you want to use.

Alternatively, you can use something like CPM which is based on CMake's Fetch_Content module.

CPMAddPackage(
    NAME magic_enum
    GITHUB_REPOSITORY Neargye/magic_enum
    GIT_TAG x.y.z # Where `x.y.z` is the release version you want to use.
)

Bazel is also supported, simply add to your WORKSPACE file:

http_archive(
    name = "magic_enum",
    strip_prefix = "magic_enum-<commit>",
    urls = ["https://github.com/Neargye/magic_enum/archive/<commit>.zip"],
)

To use bazel inside the repository it's possible to do:

bazel build //...
bazel test //...
bazel run //:example

(Note that you must use a supported compiler or specify it with export CC= <compiler>.)

Compiler compatibility

Clang/LLVM >= 5
MSVC++ >= 14.11 / Visual Studio >= 2017
Xcode >= 10
GCC >= 9
MinGW >= 9

grendello / magic_enum