1 //
2 // execution/detail/as_receiver.hpp
3 // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
4 //
5 // Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com)
6 //
7 // Distributed under the Boost Software License, Version 1.0. (See accompanying
8 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
9 //
10 
11 #ifndef BOOST_ASIO_EXECUTION_DETAIL_AS_RECEIVER_HPP
12 #define BOOST_ASIO_EXECUTION_DETAIL_AS_RECEIVER_HPP
13 
14 #if defined(_MSC_VER) && (_MSC_VER >= 1200)
15 # pragma once
16 #endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
17 
18 #include <boost/asio/detail/config.hpp>
19 #include <boost/asio/detail/type_traits.hpp>
20 #include <boost/asio/traits/set_done_member.hpp>
21 #include <boost/asio/traits/set_error_member.hpp>
22 #include <boost/asio/traits/set_value_member.hpp>
23 
24 #include <boost/asio/detail/push_options.hpp>
25 
26 namespace boost {
27 namespace asio {
28 namespace execution {
29 namespace detail {
30 
31 template <typename Function, typename>
32 struct as_receiver
33 {
34   Function f_;
35 
36   template <typename F>
as_receiverboost::asio::execution::detail::as_receiver37   explicit as_receiver(BOOST_ASIO_MOVE_ARG(F) f, int)
38     : f_(BOOST_ASIO_MOVE_CAST(F)(f))
39   {
40   }
41 
42 #if defined(BOOST_ASIO_MSVC) && defined(BOOST_ASIO_HAS_MOVE)
as_receiverboost::asio::execution::detail::as_receiver43   as_receiver(as_receiver&& other)
44     : f_(BOOST_ASIO_MOVE_CAST(Function)(other.f_))
45   {
46   }
47 #endif // defined(BOOST_ASIO_MSVC) && defined(BOOST_ASIO_HAS_MOVE)
48 
set_valueboost::asio::execution::detail::as_receiver49   void set_value()
50     BOOST_ASIO_NOEXCEPT_IF(noexcept(declval<Function&>()()))
51   {
52     f_();
53   }
54 
55   template <typename E>
set_errorboost::asio::execution::detail::as_receiver56   void set_error(E) BOOST_ASIO_NOEXCEPT
57   {
58     std::terminate();
59   }
60 
set_doneboost::asio::execution::detail::as_receiver61   void set_done() BOOST_ASIO_NOEXCEPT
62   {
63   }
64 };
65 
66 template <typename T>
67 struct is_as_receiver : false_type
68 {
69 };
70 
71 template <typename Function, typename T>
72 struct is_as_receiver<as_receiver<Function, T> > : true_type
73 {
74 };
75 
76 } // namespace detail
77 } // namespace execution
78 namespace traits {
79 
80 #if !defined(BOOST_ASIO_HAS_DEDUCED_SET_VALUE_MEMBER_TRAIT)
81 
82 template <typename Function, typename T>
83 struct set_value_member<
84     boost::asio::execution::detail::as_receiver<Function, T>, void()>
85 {
86   BOOST_ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
87 #if defined(BOOST_ASIO_HAS_NOEXCEPT)
88   BOOST_ASIO_STATIC_CONSTEXPR(bool,
89       is_noexcept = noexcept(declval<Function&>()()));
90 #else // defined(BOOST_ASIO_HAS_NOEXCEPT)
91   BOOST_ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
92 #endif // defined(BOOST_ASIO_HAS_NOEXCEPT)
93   typedef void result_type;
94 };
95 
96 #endif // !defined(BOOST_ASIO_HAS_DEDUCED_SET_VALUE_MEMBER_TRAIT)
97 
98 #if !defined(BOOST_ASIO_HAS_DEDUCED_SET_ERROR_MEMBER_TRAIT)
99 
100 template <typename Function, typename T, typename E>
101 struct set_error_member<
102     boost::asio::execution::detail::as_receiver<Function, T>, E>
103 {
104   BOOST_ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
105   BOOST_ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
106   typedef void result_type;
107 };
108 
109 #endif // !defined(BOOST_ASIO_HAS_DEDUCED_SET_ERROR_MEMBER_TRAIT)
110 
111 #if !defined(BOOST_ASIO_HAS_DEDUCED_SET_DONE_MEMBER_TRAIT)
112 
113 template <typename Function, typename T>
114 struct set_done_member<
115     boost::asio::execution::detail::as_receiver<Function, T> >
116 {
117   BOOST_ASIO_STATIC_CONSTEXPR(bool, is_valid = true);
118   BOOST_ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true);
119   typedef void result_type;
120 };
121 
122 #endif // !defined(BOOST_ASIO_HAS_DEDUCED_SET_DONE_MEMBER_TRAIT)
123 
124 } // namespace traits
125 } // namespace asio
126 } // namespace boost
127 
128 #include <boost/asio/detail/pop_options.hpp>
129 
130 #endif // BOOST_ASIO_EXECUTION_DETAIL_AS_RECEIVER_HPP
131