flags.h File Reference

#include <type_traits>

Go to the source code of this file.

Macros
#define	NX_KIT_API
#define	NX_KIT_ENABLE_FLAGS(ENUM)

Functions
template<typename Enum >
constexpr std::underlying_type< Enum >::type	nx::kit::flags_detail::toUnderlyingType (Enum value)

Detailed Description

Facilities to enable bit flags functionality for enums.

Usage example:

    #include <nx/kit/flags.h>
    #include <nx/kit/debug.h>

    enum class Color: unsigned char
    {
        black = 0,

        red = 1 << 0,
        green = 1 << 1,
        blue = 1 << 2,

        yellow = red | green,
        magenta = red | blue,
        cyan = green | blue,

        white = red | green | blue,
    };
    NX_KIT_ENABLE_FLAGS(Color);

    // Class member enumerations are supported.
    struct Border
    {
        // Unscoped enumerations are supported.
        enum CrossDirection
        {
            NoDirection = 0,
            InDirection = 1 << 0,
            OutDirection = 1 << 1,
            EitherDirection = InDirection | OutDirection,
        };
    };
    NX_KIT_ENABLE_FLAGS(Border::CrossDirection);

    int main()
    {
        NX_KIT_ASSERT((Color::magenta | Color::green & ~Color::red) == Color::cyan);
        NX_KIT_ASSERT((Border::OutDirection | Border::InDirection) == Border::EitherDirection);
    }

This header can be included in any C++ project.

Macro Definition Documentation

NX_KIT_ENABLE_FLAGS

#define NX_KIT_ENABLE_FLAGS

(

ENUM

)

Enable flag operations for a given enum. Must be invoked at namespace scope in the innermost namespace containing enum declaration.