Updated boost to v1.55.0

[rsem.git] / boost / type_traits / common_type.hpp

diff --git a/boost/type_traits/common_type.hpp b/boost/type_traits/common_type.hpp
new file mode 100644 (file)
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+++ b/boost/type_traits/common_type.hpp
@@ -0,0 +1,157 @@
+//  common_type.hpp  ---------------------------------------------------------//
+
+//  Copyright 2008 Howard Hinnant
+//  Copyright 2008 Beman Dawes
+
+//  Distributed under the Boost Software License, Version 1.0.
+//  See http://www.boost.org/LICENSE_1_0.txt
+
+#ifndef BOOST_TYPE_TRAITS_COMMON_TYPE_HPP
+#define BOOST_TYPE_TRAITS_COMMON_TYPE_HPP
+
+#include <boost/config.hpp>
+
+#if defined(__SUNPRO_CC) && !defined(BOOST_COMMON_TYPE_DONT_USE_TYPEOF)
+#  define BOOST_COMMON_TYPE_DONT_USE_TYPEOF
+#endif
+#if defined(__IBMCPP__) && !defined(BOOST_COMMON_TYPE_DONT_USE_TYPEOF)
+#  define BOOST_COMMON_TYPE_DONT_USE_TYPEOF
+#endif
+
+//----------------------------------------------------------------------------//
+#if defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES) && !defined(BOOST_COMMON_TYPE_ARITY)
+#define BOOST_COMMON_TYPE_ARITY 3
+#endif
+
+//----------------------------------------------------------------------------//
+#if defined(BOOST_NO_CXX11_DECLTYPE) && !defined(BOOST_COMMON_TYPE_DONT_USE_TYPEOF)
+#include <boost/typeof/typeof.hpp>   // boost wonders never cease!
+#endif
+
+//----------------------------------------------------------------------------//
+#ifndef BOOST_NO_CXX11_STATIC_ASSERT
+#define BOOST_COMMON_TYPE_STATIC_ASSERT(CND, MSG, TYPES) static_assert(CND,MSG)
+#elif defined(BOOST_COMMON_TYPE_USES_MPL_ASSERT)
+#include <boost/mpl/assert.hpp>
+#include <boost/mpl/bool.hpp>
+#define BOOST_COMMON_TYPE_STATIC_ASSERT(CND, MSG, TYPES)                                 \
+    BOOST_MPL_ASSERT_MSG(boost::mpl::bool_< (CND) >::type::value, MSG, TYPES)
+#else
+#include <boost/static_assert.hpp>
+#define BOOST_COMMON_TYPE_STATIC_ASSERT(CND, MSG, TYPES) BOOST_STATIC_ASSERT(CND)
+#endif
+
+#if !defined(BOOST_NO_CXX11_STATIC_ASSERT) || !defined(BOOST_COMMON_TYPE_USES_MPL_ASSERT)
+#define BOOST_COMMON_TYPE_MUST_BE_A_COMPLE_TYPE "must be complete type"
+#endif
+
+#if defined(BOOST_NO_CXX11_DECLTYPE) && defined(BOOST_COMMON_TYPE_DONT_USE_TYPEOF)
+#include <boost/type_traits/detail/common_type_imp.hpp>
+#include <boost/type_traits/remove_cv.hpp>
+#endif
+#include <boost/mpl/if.hpp>
+#include <boost/utility/declval.hpp>
+#include <boost/type_traits/add_rvalue_reference.hpp>
+
+//----------------------------------------------------------------------------//
+//                                                                            //
+//                           C++03 implementation of                          //
+//             20.9.7.6 Other transformations [meta.trans.other]              //
+//                          Written by Howard Hinnant                         //
+//      Adapted for Boost by Beman Dawes, Vicente Botet and  Jeffrey Hellrung //
+//                                                                            //
+//----------------------------------------------------------------------------//
+
+namespace boost {
+
+// prototype
+#if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES)
+    template<typename... T>
+    struct common_type;
+#else // or no specialization
+    template <class T, class U = void, class V = void>
+    struct common_type
+    {
+    public:
+        typedef typename common_type<typename common_type<T, U>::type, V>::type type;
+    };
+#endif
+
+
+// 1 arg
+    template<typename T>
+#if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES)
+    struct common_type<T>
+#else
+    struct common_type<T, void, void>
+
+#endif
+    {
+        BOOST_COMMON_TYPE_STATIC_ASSERT(sizeof(T) > 0, BOOST_COMMON_TYPE_MUST_BE_A_COMPLE_TYPE, (T));
+    public:
+        typedef T type;
+    };
+
+// 2 args
+namespace type_traits_detail {
+
+    template <class T, class U>
+    struct common_type_2
+    {
+    private:
+        BOOST_COMMON_TYPE_STATIC_ASSERT(sizeof(T) > 0, BOOST_COMMON_TYPE_MUST_BE_A_COMPLE_TYPE, (T));
+        BOOST_COMMON_TYPE_STATIC_ASSERT(sizeof(U) > 0, BOOST_COMMON_TYPE_MUST_BE_A_COMPLE_TYPE, (U));
+        static bool declval_bool();  // workaround gcc bug; not required by std
+        static typename add_rvalue_reference<T>::type declval_T();  // workaround gcc bug; not required by std
+        static typename add_rvalue_reference<U>::type declval_U();  // workaround gcc bug; not required by std
+        static typename add_rvalue_reference<bool>::type declval_b();  
+
+#if !defined(BOOST_NO_CXX11_DECLTYPE)
+    public:
+        typedef decltype(declval<bool>() ? declval<T>() : declval<U>()) type;
+#elif defined(BOOST_COMMON_TYPE_DONT_USE_TYPEOF)
+    public:
+    typedef typename detail_type_traits_common_type::common_type_impl<
+          typename remove_cv<T>::type,
+          typename remove_cv<U>::type
+      >::type type;
+#else
+    public:
+        typedef BOOST_TYPEOF_TPL(declval_b() ? declval_T() : declval_U()) type;
+#endif
+
+#if defined(__GNUC__) && __GNUC__ == 3 && (__GNUC_MINOR__ == 2 || __GNUC_MINOR__ == 3)
+    public:
+        void public_dummy_function_just_to_silence_warning();
+#endif
+    };
+
+    template <class T>
+    struct common_type_2<T, T>
+    {
+        typedef T type;
+    };
+    }
+
+#if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES)
+    template <class T, class U>
+    struct common_type<T, U>
+#else
+    template <class T, class U>
+    struct common_type<T, U, void>
+#endif
+    : public type_traits_detail::common_type_2<T,U>
+    { };
+
+
+// 3 or more args
+#if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES)
+    template<typename T, typename U, typename... V>
+    struct common_type<T, U, V...> {
+    public:
+        typedef typename common_type<typename common_type<T, U>::type, V...>::type type;
+    };
+#endif
+}  // namespace boost
+
+#endif  // BOOST_TYPE_TRAITS_COMMON_TYPE_HPP