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

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.
enum_fuse allows multidimensional switch/cases.
enum_switch allows runtime enum value transformation to constexpr context.
enum_for_each calls a function with all enum constexpr value.
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" 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"

Enum fusion for multi-level switch/case statements

switch (magic_enum::enum_fuse(color, direction).value()) {
  case magic_enum::enum_fuse(Color::RED, Directions::Up).value(): // ...
  case magic_enum::enum_fuse(Color::BLUE, Directions::Down).value(): // ...
// ...
}

Enum switch runtime value as constexpr constant

Color color = Color::RED;

magic_enum::enum_switch([] (auto val) {
  constexpr Color c_color = val;
  // ...
}, color);

Enum iterate for each enum as constexpr constant

magic_enum::enum_for_each<Color>([] (auto val) {
  constexpr Color c_color = val;
  // ...
});

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.

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.
If you are using Build2 to build and manage your dependencies, add depends: magic_enum ^x.y.z to the manifest file where x.y.z is the release version you want to use. You can then import the target using magic_enum%lib{magic_enum}.

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>.)

If you are using Ros, you can include this package by adding <depend>magic_enum</depend> to your package.xml and include this package in your workspace. In your CMakeLists.txt add the following:
```
find_package(magic_enum CONFIG REQUIRED)
...
target_link_libraries(your_executable magic_enum::magic_enum)
```

Compiler compatibility

Clang/LLVM >= 6
MSVC++ >= 14.11 / Visual Studio >= 2017
Xcode >= 10
GCC >= 9
MinGW >= 9

spotx / magic_enum