--- /dev/null
+#ifndef BOOST_BIND_DETAIL_RESULT_TRAITS_HPP_INCLUDED
+#define BOOST_BIND_DETAIL_RESULT_TRAITS_HPP_INCLUDED
+
+// MS compatible compilers support #pragma once
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1020)
+# pragma once
+#endif
+
+//
+// bind/detail/result_traits.hpp
+//
+// boost/bind.hpp support header, return type deduction
+//
+// Copyright 2006, 2020 Peter Dimov
+//
+// Distributed under the Boost Software License, Version 1.0.
+// See accompanying file LICENSE_1_0.txt or copy at
+// http://www.boost.org/LICENSE_1_0.txt
+//
+// See http://www.boost.org/libs/bind/bind.html for documentation.
+//
+
+#if defined(_MSVC_LANG) && _MSVC_LANG >= 17
+#include <functional>
+#endif
+
+namespace boost
+{
+
+namespace _bi
+{
+
+template<class R, class F> struct result_traits
+{
+ typedef R type;
+};
+
+struct unspecified {};
+
+template<class F> struct result_traits<unspecified, F>
+{
+ typedef typename F::result_type type;
+};
+
+template<class F> struct result_traits< unspecified, reference_wrapper<F> >
+{
+ typedef typename F::result_type type;
+};
+
+#if defined(_MSVC_LANG) && _MSVC_LANG >= 17
+
+template<class T> struct result_traits< unspecified, std::plus<T> >
+{
+ typedef T type;
+};
+
+template<class T> struct result_traits< unspecified, std::minus<T> >
+{
+ typedef T type;
+};
+
+template<class T> struct result_traits< unspecified, std::multiplies<T> >
+{
+ typedef T type;
+};
+
+template<class T> struct result_traits< unspecified, std::divides<T> >
+{
+ typedef T type;
+};
+
+template<class T> struct result_traits< unspecified, std::modulus<T> >
+{
+ typedef T type;
+};
+
+template<class T> struct result_traits< unspecified, std::negate<T> >
+{
+ typedef T type;
+};
+
+template<class T> struct result_traits< unspecified, std::equal_to<T> >
+{
+ typedef bool type;
+};
+
+template<class T> struct result_traits< unspecified, std::not_equal_to<T> >
+{
+ typedef bool type;
+};
+
+template<class T> struct result_traits< unspecified, std::greater<T> >
+{
+ typedef bool type;
+};
+
+template<class T> struct result_traits< unspecified, std::less<T> >
+{
+ typedef bool type;
+};
+
+template<class T> struct result_traits< unspecified, std::greater_equal<T> >
+{
+ typedef bool type;
+};
+
+template<class T> struct result_traits< unspecified, std::less_equal<T> >
+{
+ typedef bool type;
+};
+
+template<class T> struct result_traits< unspecified, std::logical_and<T> >
+{
+ typedef bool type;
+};
+
+template<class T> struct result_traits< unspecified, std::logical_or<T> >
+{
+ typedef bool type;
+};
+
+template<class T> struct result_traits< unspecified, std::logical_not<T> >
+{
+ typedef bool type;
+};
+
+template<class T> struct result_traits< unspecified, std::bit_and<T> >
+{
+ typedef T type;
+};
+
+template<class T> struct result_traits< unspecified, std::bit_or<T> >
+{
+ typedef T type;
+};
+
+template<class T> struct result_traits< unspecified, std::bit_xor<T> >
+{
+ typedef T type;
+};
+
+template<class T> struct result_traits< unspecified, std::bit_not<T> >
+{
+ typedef T type;
+};
+
+#endif
+
+} // namespace _bi
+
+} // namespace boost
+
+#endif // #ifndef BOOST_BIND_DETAIL_RESULT_TRAITS_HPP_INCLUDED