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-rw-r--r--boost/type_traits/has_plus_assign.hpp90
1 files changed, 90 insertions, 0 deletions
diff --git a/boost/type_traits/has_plus_assign.hpp b/boost/type_traits/has_plus_assign.hpp
index 5ef6f23289..b4d05ad2ea 100644
--- a/boost/type_traits/has_plus_assign.hpp
+++ b/boost/type_traits/has_plus_assign.hpp
@@ -9,6 +9,95 @@
#ifndef BOOST_TT_HAS_PLUS_ASSIGN_HPP_INCLUDED
#define BOOST_TT_HAS_PLUS_ASSIGN_HPP_INCLUDED
+#include <boost/config.hpp>
+#include <boost/type_traits/detail/config.hpp>
+
+// cannot include this header without getting warnings of the kind:
+// gcc:
+// warning: value computed is not used
+// warning: comparison between signed and unsigned integer expressions
+// msvc:
+// warning C4018: '<' : signed/unsigned mismatch
+// warning C4244: '+=' : conversion from 'double' to 'char', possible loss of data
+// warning C4547: '*' : operator before comma has no effect; expected operator with side-effect
+// warning C4800: 'int' : forcing value to bool 'true' or 'false' (performance warning)
+// warning C4804: '<' : unsafe use of type 'bool' in operation
+// warning C4805: '==' : unsafe mix of type 'bool' and type 'char' in operation
+// cannot find another implementation -> declared as system header to suppress these warnings.
+#if defined(__GNUC__)
+# pragma GCC system_header
+#elif defined(BOOST_MSVC)
+# pragma warning ( push )
+# pragma warning ( disable : 4018 4244 4547 4800 4804 4805 4913 4133)
+# if BOOST_WORKAROUND(BOOST_MSVC_FULL_VER, >= 140050000)
+# pragma warning ( disable : 6334)
+# endif
+#endif
+
+#if defined(BOOST_TT_HAS_ACCURATE_BINARY_OPERATOR_DETECTION)
+
+#include <boost/type_traits/integral_constant.hpp>
+#include <boost/type_traits/make_void.hpp>
+#include <boost/type_traits/is_convertible.hpp>
+#include <boost/type_traits/is_void.hpp>
+#include <boost/type_traits/is_same.hpp>
+#include <boost/type_traits/is_pointer.hpp>
+#include <boost/type_traits/is_arithmetic.hpp>
+#include <boost/type_traits/add_reference.hpp>
+#include <boost/type_traits/remove_pointer.hpp>
+#include <boost/type_traits/remove_reference.hpp>
+#include <boost/type_traits/remove_cv.hpp>
+#include <utility>
+
+namespace boost
+{
+
+ namespace binary_op_detail {
+
+ struct dont_care;
+
+ template <class T, class U, class Ret, class = boost::void_t<>>
+ struct has_plus_assign_ret_imp : public boost::false_type {};
+
+ template <class T, class U, class Ret>
+ struct has_plus_assign_ret_imp<T, U, Ret, boost::void_t<decltype(std::declval<typename add_reference<T>::type>() += std::declval<typename add_reference<U>::type>())> >
+ : public boost::integral_constant<bool, ::boost::is_convertible<decltype(std::declval<typename add_reference<T>::type>() += std::declval<typename add_reference<U>::type>()), Ret>::value> {};
+
+ template <class T, class U, class = boost::void_t<> >
+ struct has_plus_assign_void_imp : public boost::false_type {};
+
+ template <class T, class U>
+ struct has_plus_assign_void_imp<T, U, boost::void_t<decltype(std::declval<typename add_reference<T>::type>() += std::declval<typename add_reference<U>::type>())> >
+ : public boost::integral_constant<bool, ::boost::is_void<decltype(std::declval<typename add_reference<T>::type>() += std::declval<typename add_reference<U>::type>())>::value> {};
+
+ template <class T, class U, class = boost::void_t<>>
+ struct has_plus_assign_dc_imp : public boost::false_type {};
+
+ template <class T, class U>
+ struct has_plus_assign_dc_imp<T, U, boost::void_t<decltype(std::declval<typename add_reference<T>::type>() += std::declval<typename add_reference<U>::type>())> >
+ : public boost::true_type {};
+
+ template <class T, class U, class Ret>
+ struct has_plus_assign_filter_ret : public boost::binary_op_detail:: has_plus_assign_ret_imp <T, U, Ret> {};
+ template <class T, class U>
+ struct has_plus_assign_filter_ret<T, U, void> : public boost::binary_op_detail:: has_plus_assign_void_imp <T, U> {};
+ template <class T, class U>
+ struct has_plus_assign_filter_ret<T, U, boost::binary_op_detail::dont_care> : public boost::binary_op_detail:: has_plus_assign_dc_imp <T, U> {};
+
+ template <class T, class U, class Ret, bool f>
+ struct has_plus_assign_filter_impossible : public boost::binary_op_detail:: has_plus_assign_filter_ret <T, U, Ret> {};
+ template <class T, class U, class Ret>
+ struct has_plus_assign_filter_impossible<T, U, Ret, true> : public boost::false_type {};
+
+ }
+
+ template <class T, class U = T, class Ret = boost::binary_op_detail::dont_care>
+ struct has_plus_assign : public boost::binary_op_detail:: has_plus_assign_filter_impossible <T, U, Ret, boost::is_arithmetic<typename boost::remove_reference<T>::type>::value && boost::is_pointer<typename remove_reference<U>::type>::value && !boost::is_same<bool, typename boost::remove_cv<typename remove_reference<T>::type>::type>::value> {};
+
+}
+
+#else
+
#define BOOST_TT_TRAIT_NAME has_plus_assign
#define BOOST_TT_TRAIT_OP +=
#define BOOST_TT_FORBIDDEN_IF\
@@ -64,3 +153,4 @@
#undef BOOST_TT_FORBIDDEN_IF
#endif
+#endif