1#ifndef BOOST_TT_IS_ABSTRACT_CLASS_HPP
2#define BOOST_TT_IS_ABSTRACT_CLASS_HPP
3
4#if defined(_MSC_VER)
5# pragma once
6#endif
7
8/////////1/////////2/////////3/////////4/////////5/////////6/////////7/////////8
9// is_abstract_class.hpp:
10//
11// (C) Copyright 2002 Rani Sharoni ([email protected]) and Robert Ramey
12// Use, modification and distribution is subject to the Boost Software
13// License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
14// http://www.boost.org/LICENSE_1_0.txt)
15//
16// See http://www.boost.org for updates, documentation, and revision history.
17//
18
19// Compile type discovery whether given type is abstract class or not.
20//
21// Requires DR 337 to be supported by compiler
22// (http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#337).
23//
24//
25// Believed (Jan 2004) to work on:
26// - GCC 3.4
27// - VC++ 7.1
28// - compilers with new EDG frontend (Intel C++ 7, Comeau 4.3.2)
29//
30// Doesn't work on:
31// - VC++6, VC++7.0 and less
32// - GCC 3.3.X and less
33// - Borland C++ 6 and less
34//
35//
36// History:
37// - Originally written by Rani Sharoni, see
38// http://groups.google.com/groups?selm=df893da6.0207110613.75b2fe90%40posting.google.com
39// At this time supported by EDG (Intel C++ 7, Comeau 4.3.2) and VC7.1.
40// - Adapted and added into Boost.Serialization library by Robert Ramey
41// (starting with submission #10).
42// - Jan 2004: GCC 3.4 fixed to support DR337 (Giovanni Bajo).
43// - Jan 2004: modified to be part of Boost.TypeTraits (Pavel Vozenilek).
44// - Nov 2004: Christoph Ludwig found that the implementation did not work with
45// template types and gcc-3.4 or VC7.1, fix due to Christoph Ludwig
46// and John Maddock.
47// - Dec 2004: Added new config macro BOOST_NO_IS_ABSTRACT which causes the template
48// to degrade gracefully, rather than trash the compiler (John Maddock).
49//
50
51#include <boost/type_traits/intrinsics.hpp>
52#ifndef BOOST_IS_ABSTRACT
53#include <boost/static_assert.hpp>
54#include <boost/type_traits/detail/yes_no_type.hpp>
55#include <boost/type_traits/is_class.hpp>
56#include <boost/type_traits/detail/ice_and.hpp>
57#ifdef BOOST_NO_IS_ABSTRACT
58#include <boost/type_traits/is_polymorphic.hpp>
59#endif
60#endif
61// should be the last #include
62#include <boost/type_traits/detail/bool_trait_def.hpp>
63
64
65namespace boost {
66namespace detail{
67
68#ifdef BOOST_IS_ABSTRACT
69template <class T>
70struct is_abstract_imp
71{
72 BOOST_STATIC_CONSTANT(bool, value = BOOST_IS_ABSTRACT(T));
73};
74#elif !defined(BOOST_NO_IS_ABSTRACT)
75template<class T>
76struct is_abstract_imp2
77{
78 // Deduction fails if T is void, function type,
79 // reference type (14.8.2/2)or an abstract class type
80 // according to review status issue #337
81 //
82 template<class U>
83 static type_traits::no_type check_sig(U (*)[1]);
84 template<class U>
85 static type_traits::yes_type check_sig(...);
86 //
87 // T must be a complete type, further if T is a template then
88 // it must be instantiated in order for us to get the right answer:
89 //
90 BOOST_STATIC_ASSERT(sizeof(T) != 0);
91
92 // GCC2 won't even parse this template if we embed the computation
93 // of s1 in the computation of value.
94#ifdef __GNUC__
95 BOOST_STATIC_CONSTANT(std::size_t, s1 = sizeof(is_abstract_imp2<T>::template check_sig<T>(0)));
96#else
97#if BOOST_WORKAROUND(BOOST_MSVC_FULL_VER, >= 140050000)
98#pragma warning(push)
99#pragma warning(disable:6334)
100#endif
101 BOOST_STATIC_CONSTANT(std::size_t, s1 = sizeof(check_sig<T>(0)));
102#if BOOST_WORKAROUND(BOOST_MSVC_FULL_VER, >= 140050000)
103#pragma warning(pop)
104#endif
105#endif
106
107 BOOST_STATIC_CONSTANT(bool, value =
108 (s1 == sizeof(type_traits::yes_type)));
109};
110
111template <bool v>
112struct is_abstract_select
113{
114 template <class T>
115 struct rebind
116 {
117 typedef is_abstract_imp2<T> type;
118 };
119};
120template <>
121struct is_abstract_select<false>
122{
123 template <class T>
124 struct rebind
125 {
126 typedef false_type type;
127 };
128};
129
130template <class T>
131struct is_abstract_imp
132{
133 typedef is_abstract_select< ::boost::is_class<T>::value> selector;
134 typedef typename selector::template rebind<T> binder;
135 typedef typename binder::type type;
136
137 BOOST_STATIC_CONSTANT(bool, value = type::value);
138};
139
140#endif
141}
142
143#ifndef BOOST_NO_IS_ABSTRACT
144BOOST_TT_AUX_BOOL_TRAIT_DEF1(is_abstract,T,::boost::detail::is_abstract_imp<T>::value)
145#else
146BOOST_TT_AUX_BOOL_TRAIT_DEF1(is_abstract,T,::boost::detail::is_polymorphic_imp<T>::value)
147#endif
148
149} // namespace boost
150
151#include <boost/type_traits/detail/bool_trait_undef.hpp>
152
153#endif //BOOST_TT_IS_ABSTRACT_CLASS_HPP
154