magic_enum/README.md

# Magic Enum C++

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

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## What is Magic Enum?

Header-only C++17 library provides Enum-to-String and String-to-Enum and other useful functions, without any macro or boilerplate code.
* `magic_enum::enum_cast` obtains enum value from string or integer.
* `magic_enum::enum_value` obtains indexed access to enum value.
* `magic_enum::enum_values` obtains enum value sequence.
* `magic_enum::enum_count` obtains number of enum values.
* `magic_enum::enum_name` obtains string name from enum value.
* `magic_enum::enum_names` obtains string enum name sequence.

## Features

* C++17
* Header-only
* Dependency-free
* Compile-time
* Enum to string
* String to enum
* Works with any enum type

## [Examples](example/example.cpp)

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

* Enum value to string
  ```cpp
  Color color = Color::RED;
  auto color_name = magic_enum::enum_name(color);
  if (color_name.has_value()) {
    // color_name.value() -> "RED"
  }
  ```

* Static storage enum variable to string
  ```cpp
  constexpr Color color = Color::BLUE;
  constexpr auto color_name = magic_enum::enum_name(color);
  if (color_name.has_value()) {
    // color_name.value() -> "BLUE"
  }
  ```

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

* Static storage string to enum value
  ```cpp
  constexpr auto color = magic_enum::enum_cast<Color>("BLUE");
  if (color.has_value()) {
    // color.value() -> Color::BLUE
  }
  ```

* Integer to enum value
  ```cpp
  int color_value = 2;
  auto color = magic_enum::enum_cast<Color>(color_value);
  if (colo.has_value()) {
    // color.value() -> Color::RED
  }
  ```

* Static storage integer to enum value
  ```cpp
  constexpr auto color = magic_enum::enum_cast<Color>(4);
  if (color.has_value()) {
    // color.value() -> Color::BLUE
  }
  ```

* Indexed access to enum value
  ```cpp
  int i = 1;
  Color colo = magic_enum::enum_value<Color>(i);
  // color -> Color::BLUE
  ```

* Compile-time indexed access.
  ```cpp
  constexpr Color color = magic_enum::enum_value<Color>(0);
  // color -> Color::RED
  ```

* Enum value sequence
  ```cpp
  constexpr auto colors = magic_enum::enum_values<Color>();
  // colors -> {Color::RED, Color::BLUE, Color::GREEN}
  ```

* Number of enum elements
  ```cpp
  constexpr std::size_t color_count = magic_enum::enum_count<Color>();
  // color_count -> 3
  ```

* Enum names sequence
  ```cpp
  constexpr auto color_names = magic_enum::enum_names<Color>();
  // color_names -> {"RED", "BLUE", "GREEN"}
  ```

* Stream operator for enum
  ```cpp
  using namespace magic_enum::ops; // out-of-the-box stream operator for enums.
  Color color = Color::BLUE;
  std::cout << color << std::endl; // "BLUE"
  ```

## Remarks

* `magic_enum::enum_cast` returns `std::optional<E>`, using `has_value()` to check contains enum value and `value()` to get the enum value.

* `magic_enum::enum_values` returns `std::array<E, N>` with all enum value where `N = number of enum values`, sorted by enum value.

* `magic_enum::enum_name` returns `std::optional<std::string_view>`, using `has_value()` to check contains enum name and `value()` to get the enum name.

* `magic_enum::enum_names` returns `std::array<std::string_view, N>` with all string enum name where `N = number of enum values`, sorted by enum value.

* Enum value must be in range `(-MAGIC_ENUM_RANGE, MAGIC_ENUM_RANGE)`. By default `MAGIC_ENUM_RANGE = 256`. If you need a larger range, redefine the macro `MAGIC_ENUM_RANGE`.
  ```cpp
  #define MAGIC_ENUM_RANGE 1024 // Redefine MAGIC_ENUM_RANGE for larger range.
  #include <magic_enum.hpp>
  ```

## Integration

You should add the required file [magic_enum.hpp](include/magic_enum.hpp).

## Compiler compatibility

* Clang/LLVM >= 5
* Visual C++ >= 15.3 / Visual Studio >= 2017
* Xcode >= 10.2
* GCC >= 9

## Licensed under the [MIT License](LICENSE)