1// scoped_enum.hpp ---------------------------------------------------------//
2
3// Copyright Beman Dawes, 2009
4// Copyright (C) 2011-2012 Vicente J. Botet Escriba
5// Copyright (C) 2012 Anthony Williams
6
7// Distributed under the Boost Software License, Version 1.0.
8// See http://www.boost.org/LICENSE_1_0.txt
9
10#ifndef BOOST_CORE_SCOPED_ENUM_HPP
11#define BOOST_CORE_SCOPED_ENUM_HPP
12
13#include <boost/config.hpp>
14
15#ifdef BOOST_HAS_PRAGMA_ONCE
16#pragma once
17#endif
18
19namespace boost
20{
21
22#ifdef BOOST_NO_CXX11_SCOPED_ENUMS
23
24 /**
25 * Meta-function to get the native enum type associated to an enum class or its emulation.
26 */
27 template <typename EnumType>
28 struct native_type
29 {
30 /**
31 * The member typedef type names the native enum type associated to the scoped enum,
32 * which is it self if the compiler supports scoped enums or EnumType::enum_type if it is an emulated scoped enum.
33 */
34 typedef typename EnumType::enum_type type;
35 };
36
37 /**
38 * Casts a scoped enum to its underlying type.
39 *
40 * This function is useful when working with scoped enum classes, which doens't implicitly convert to the underlying type.
41 * @param v A scoped enum.
42 * @returns The underlying type.
43 * @throws No-throws.
44 */
45 template <typename UnderlyingType, typename EnumType>
46 inline
47 BOOST_CONSTEXPR UnderlyingType underlying_cast(EnumType v) BOOST_NOEXCEPT
48 {
49 return v.get_underlying_value_();
50 }
51
52 /**
53 * Casts a scoped enum to its native enum type.
54 *
55 * This function is useful to make programs portable when the scoped enum emulation can not be use where native enums can.
56 *
57 * EnumType the scoped enum type
58 *
59 * @param v A scoped enum.
60 * @returns The native enum value.
61 * @throws No-throws.
62 */
63 template <typename EnumType>
64 inline
65 BOOST_CONSTEXPR typename EnumType::enum_type native_value(EnumType e) BOOST_NOEXCEPT
66 {
67 return e.get_native_value_();
68 }
69
70#else // BOOST_NO_CXX11_SCOPED_ENUMS
71
72 template <typename EnumType>
73 struct native_type
74 {
75 typedef EnumType type;
76 };
77
78 template <typename UnderlyingType, typename EnumType>
79 inline
80 BOOST_CONSTEXPR UnderlyingType underlying_cast(EnumType v) BOOST_NOEXCEPT
81 {
82 return static_cast<UnderlyingType>(v);
83 }
84
85 template <typename EnumType>
86 inline
87 BOOST_CONSTEXPR EnumType native_value(EnumType e) BOOST_NOEXCEPT
88 {
89 return e;
90 }
91
92#endif // BOOST_NO_CXX11_SCOPED_ENUMS
93}
94
95
96#ifdef BOOST_NO_CXX11_SCOPED_ENUMS
97
98#ifndef BOOST_NO_CXX11_EXPLICIT_CONVERSION_OPERATORS
99
100#define BOOST_SCOPED_ENUM_UT_DECLARE_CONVERSION_OPERATOR \
101 explicit BOOST_CONSTEXPR operator underlying_type() const BOOST_NOEXCEPT { return get_underlying_value_(); }
102
103#else
104
105#define BOOST_SCOPED_ENUM_UT_DECLARE_CONVERSION_OPERATOR
106
107#endif
108
109/**
110 * Start a declaration of a scoped enum.
111 *
112 * @param EnumType The new scoped enum.
113 * @param UnderlyingType The underlying type.
114 */
115#define BOOST_SCOPED_ENUM_UT_DECLARE_BEGIN(EnumType, UnderlyingType) \
116 struct EnumType { \
117 typedef void is_boost_scoped_enum_tag; \
118 typedef UnderlyingType underlying_type; \
119 EnumType() BOOST_NOEXCEPT {} \
120 explicit BOOST_CONSTEXPR EnumType(underlying_type v) BOOST_NOEXCEPT : v_(v) {} \
121 BOOST_CONSTEXPR underlying_type get_underlying_value_() const BOOST_NOEXCEPT { return v_; } \
122 BOOST_SCOPED_ENUM_UT_DECLARE_CONVERSION_OPERATOR \
123 private: \
124 underlying_type v_; \
125 typedef EnumType self_type; \
126 public: \
127 enum enum_type
128
129#define BOOST_SCOPED_ENUM_DECLARE_END2() \
130 BOOST_CONSTEXPR enum_type get_native_value_() const BOOST_NOEXCEPT { return enum_type(v_); } \
131 friend BOOST_CONSTEXPR bool operator ==(self_type lhs, self_type rhs) BOOST_NOEXCEPT { return enum_type(lhs.v_)==enum_type(rhs.v_); } \
132 friend BOOST_CONSTEXPR bool operator ==(self_type lhs, enum_type rhs) BOOST_NOEXCEPT { return enum_type(lhs.v_)==rhs; } \
133 friend BOOST_CONSTEXPR bool operator ==(enum_type lhs, self_type rhs) BOOST_NOEXCEPT { return lhs==enum_type(rhs.v_); } \
134 friend BOOST_CONSTEXPR bool operator !=(self_type lhs, self_type rhs) BOOST_NOEXCEPT { return enum_type(lhs.v_)!=enum_type(rhs.v_); } \
135 friend BOOST_CONSTEXPR bool operator !=(self_type lhs, enum_type rhs) BOOST_NOEXCEPT { return enum_type(lhs.v_)!=rhs; } \
136 friend BOOST_CONSTEXPR bool operator !=(enum_type lhs, self_type rhs) BOOST_NOEXCEPT { return lhs!=enum_type(rhs.v_); } \
137 friend BOOST_CONSTEXPR bool operator <(self_type lhs, self_type rhs) BOOST_NOEXCEPT { return enum_type(lhs.v_)<enum_type(rhs.v_); } \
138 friend BOOST_CONSTEXPR bool operator <(self_type lhs, enum_type rhs) BOOST_NOEXCEPT { return enum_type(lhs.v_)<rhs; } \
139 friend BOOST_CONSTEXPR bool operator <(enum_type lhs, self_type rhs) BOOST_NOEXCEPT { return lhs<enum_type(rhs.v_); } \
140 friend BOOST_CONSTEXPR bool operator <=(self_type lhs, self_type rhs) BOOST_NOEXCEPT { return enum_type(lhs.v_)<=enum_type(rhs.v_); } \
141 friend BOOST_CONSTEXPR bool operator <=(self_type lhs, enum_type rhs) BOOST_NOEXCEPT { return enum_type(lhs.v_)<=rhs; } \
142 friend BOOST_CONSTEXPR bool operator <=(enum_type lhs, self_type rhs) BOOST_NOEXCEPT { return lhs<=enum_type(rhs.v_); } \
143 friend BOOST_CONSTEXPR bool operator >(self_type lhs, self_type rhs) BOOST_NOEXCEPT { return enum_type(lhs.v_)>enum_type(rhs.v_); } \
144 friend BOOST_CONSTEXPR bool operator >(self_type lhs, enum_type rhs) BOOST_NOEXCEPT { return enum_type(lhs.v_)>rhs; } \
145 friend BOOST_CONSTEXPR bool operator >(enum_type lhs, self_type rhs) BOOST_NOEXCEPT { return lhs>enum_type(rhs.v_); } \
146 friend BOOST_CONSTEXPR bool operator >=(self_type lhs, self_type rhs) BOOST_NOEXCEPT { return enum_type(lhs.v_)>=enum_type(rhs.v_); } \
147 friend BOOST_CONSTEXPR bool operator >=(self_type lhs, enum_type rhs) BOOST_NOEXCEPT { return enum_type(lhs.v_)>=rhs; } \
148 friend BOOST_CONSTEXPR bool operator >=(enum_type lhs, self_type rhs) BOOST_NOEXCEPT { return lhs>=enum_type(rhs.v_); } \
149 };
150
151#define BOOST_SCOPED_ENUM_DECLARE_END(EnumType) \
152 ; \
153 BOOST_CONSTEXPR EnumType(enum_type v) BOOST_NOEXCEPT : v_(v) {} \
154 BOOST_SCOPED_ENUM_DECLARE_END2()
155
156/**
157 * Starts a declaration of a scoped enum with the default int underlying type.
158 *
159 * @param EnumType The new scoped enum.
160 */
161#define BOOST_SCOPED_ENUM_DECLARE_BEGIN(EnumType) \
162 BOOST_SCOPED_ENUM_UT_DECLARE_BEGIN(EnumType,int)
163
164/**
165 * Name of the native enum type.
166 *
167 * @param EnumType The new scoped enum.
168 */
169#define BOOST_SCOPED_ENUM_NATIVE(EnumType) EnumType::enum_type
170/**
171 * Forward declares an scoped enum.
172 *
173 * @param EnumType The scoped enum.
174 */
175#define BOOST_SCOPED_ENUM_FORWARD_DECLARE(EnumType) struct EnumType
176
177#else // BOOST_NO_CXX11_SCOPED_ENUMS
178
179#define BOOST_SCOPED_ENUM_UT_DECLARE_BEGIN(EnumType,UnderlyingType) enum class EnumType : UnderlyingType
180#define BOOST_SCOPED_ENUM_DECLARE_BEGIN(EnumType) enum class EnumType
181#define BOOST_SCOPED_ENUM_DECLARE_END2()
182#define BOOST_SCOPED_ENUM_DECLARE_END(EnumType) ;
183
184#define BOOST_SCOPED_ENUM_NATIVE(EnumType) EnumType
185#define BOOST_SCOPED_ENUM_FORWARD_DECLARE(EnumType) enum class EnumType
186
187#endif // BOOST_NO_CXX11_SCOPED_ENUMS
188
189// Deprecated macros
190#define BOOST_SCOPED_ENUM_START(name) BOOST_SCOPED_ENUM_DECLARE_BEGIN(name)
191#define BOOST_SCOPED_ENUM_END BOOST_SCOPED_ENUM_DECLARE_END2()
192#define BOOST_SCOPED_ENUM(name) BOOST_SCOPED_ENUM_NATIVE(name)
193
194#endif // BOOST_CORE_SCOPED_ENUM_HPP
195