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// scoped_enum_emulation.hpp ---------------------------------------------------------//
// Copyright Beman Dawes, 2009
// Distributed under the Boost Software License, Version 1.0.
// See http://www.boost.org/LICENSE_1_0.txt
// Generates C++0x scoped enums if the feature is present, otherwise emulates C++0x
// scoped enums with C++03 namespaces and enums. The Boost.Config BOOST_NO_SCOPED_ENUMS
// macro is used to detect feature support.
//
// See http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2007/n2347.pdf for a
// description of the scoped enum feature. Note that the committee changed the name
// from strongly typed enum to scoped enum.
//
// Caution: only the syntax is emulated; the semantics are not emulated and
// the syntax emulation doesn't include being able to specify the underlying
// representation type.
//
// The emulation is via struct rather than namespace to allow use within classes.
// Thanks to Andrey Semashev for pointing that out.
//
// Helpful comments and suggestions were also made by Kjell Elster, Phil Endecott,
// Joel Falcou, Mathias Gaunard, Felipe Magno de Almeida, Matt Calabrese, Vincente
// Botet, and Daniel James.
//
// Sample usage:
//
// BOOST_SCOPED_ENUM_START(algae) { green, red, cyan }; BOOST_SCOPED_ENUM_END
// ...
// BOOST_SCOPED_ENUM(algae) sample( algae::red );
// void foo( BOOST_SCOPED_ENUM(algae) color );
// ...
// sample = algae::green;
// foo( algae::cyan );
#ifndef BOOST_SCOPED_ENUM_EMULATION_HPP
#define BOOST_SCOPED_ENUM_EMULATION_HPP
#include <boost/config.hpp>
#ifdef BOOST_NO_SCOPED_ENUMS
# define BOOST_SCOPED_ENUM_START(name) struct name { enum enum_type
# define BOOST_SCOPED_ENUM_END };
# define BOOST_SCOPED_ENUM(name) name::enum_type
#else
# define BOOST_SCOPED_ENUM_START(name) enum class name
# define BOOST_SCOPED_ENUM_END
# define BOOST_SCOPED_ENUM(name) name
#endif
#endif // BOOST_SCOPED_ENUM_EMULATION_HPP