added connect_result_t and work towards basic_operation

include/beman/execution26/detail/basic_operation.hpp

@@ -0,0 +1,34 @@
+// include/beman/execution26/detail/basic_operation.hpp               -*-C++-*-
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+
+#ifndef INCLUDED_BEMAN_EXECUTION26_DETAIL_BASIC_OPERATION
+#define INCLUDED_BEMAN_EXECUTION26_DETAIL_BASIC_OPERATION
+
+#include <beman/execution26/detail/basic_state.hpp>
+#include <beman/execution26/detail/state_type.hpp>
+#include <beman/execution26/detail/valid_specialization.hpp>
+#include <utility>
+
+// ----------------------------------------------------------------------------
+
+namespace beman::execution26::detail
+{
+    template <typename Sender, typename Receiver>
+        requires ::beman::execution26::detail::valid_specialization<
+            ::beman::execution26::detail::state_type, Sender, Receiver
+        >
+    struct basic_operation
+        : ::beman::execution26::detail::basic_state<Sender, Receiver>
+    {
+        basic_operation(Sender&& sender, Receiver&& receiver) noexcept(true/*-dk:TODO*/)
+            : ::beman::execution26::detail::basic_state<Sender, Receiver>(
+                ::std::forward<Sender>(sender), ::std::move(receiver)
+            )
+        {
+        }
+    };
+}
+
+// ----------------------------------------------------------------------------
+
+#endif

include/beman/execution26/detail/connect.hpp

@@ -39,7 +39,7 @@ namespace beman::execution26
             }
             else
             {
-                static_assert(::std::same_as<int, Sender>);
+                static_assert(::std::same_as<int, Sender>, "can't connect the sender");
             }
         }
     };

include/beman/execution26/detail/connect_all.hpp

@@ -0,0 +1,27 @@
+// include/beman/execution26/detail/connect_all.hpp                   -*-C++-*-
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+
+#ifndef INCLUDED_BEMAN_EXECUTION26_DETAIL_CONNECT_ALL
+#define INCLUDED_BEMAN_EXECUTION26_DETAIL_CONNECT_ALL
+
+// ----------------------------------------------------------------------------
+
+namespace beman::execution26::detail
+{
+    struct connect_all_t
+    {
+        template <typename Sender, typename Receiver>
+        struct state
+        {
+        };
+        auto operator()(auto&&...) const noexcept(true/*-dk:TODO*/)
+        {
+            return 0;
+        }
+    };
+    inline constexpr connect_all_t connect_all{};
+}
+
+// ----------------------------------------------------------------------------
+
+#endif

include/beman/execution26/detail/connect_result_t.hpp

@@ -0,0 +1,22 @@
+// include/beman/execution26/detail/connect_result_t.hpp              -*-C++-*-
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+
+#ifndef INCLUDED_BEMAN_EXECUTION26_DETAIL_CONNECT_RESULT
+#define INCLUDED_BEMAN_EXECUTION26_DETAIL_CONNECT_RESULT
+
+#include <beman/execution26/detail/connect.hpp>
+#include <type_traits>
+
+// ----------------------------------------------------------------------------
+
+namespace beman::execution26
+{
+    template <typename Sender, typename Receiver>
+    using connect_result_t
+        = decltype(::beman::execution26::connect(::std::declval<Sender>(),
+                                                 ::std::declval<Receiver>()));
+}
+
+// ----------------------------------------------------------------------------
+
+#endif

src/beman/execution26/tests/exec-snd-expos.pass.cpp

@@ -1,6 +1,8 @@
 // src/beman/execution26/tests/exe-snd-expos.pass.cpp                 -*-C++-*-
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 
+#include <beman/execution26/detail/basic_operation.hpp>
+#include <beman/execution26/detail/connect_all.hpp>
 #include <beman/execution26/detail/fwd_env.hpp>
 #include <beman/execution26/detail/make_env.hpp>
 #include <beman/execution26/detail/join_env.hpp>
@@ -88,6 +90,23 @@ namespace
         auto operator== (scheduler const&) const -> bool = default;
     };
 
+    struct tag {};
+
+    struct sender0
+    {
+        using sender_concept = test_std::sender_t;
+        tag t{};
+        int data{};
+    };
+
+    struct receiver
+    {
+        using receiver_concept = test_std::receiver_t;
+        auto set_value(auto&&...) noexcept -> void {}
+        auto set_error(auto&&) noexcept -> void {}
+        auto set_stopped() noexcept -> void {}
+    };
+
     // ------------------------------------------------------------------------
 
     template <bool Expect, typename Query>
@@ -746,6 +765,29 @@ namespace
         static_assert(not test_detail::completion_tag<int>);
         static_assert(not test_detail::completion_tag<no_completion>);
     }
+
+    auto test_connect_all() -> void
+    {
+        {
+            sender0 s{};
+            test_detail::basic_state state{std::move(s), receiver{}};
+            auto product{test_detail::connect_all(&state, std::move(s), std::index_sequence<>{})};
+            (void)product;
+        }
+        {
+            sender0 const s{};
+            test_detail::basic_state state{std::move(s), receiver{}};
+            auto product{test_detail::connect_all(&state, s, std::index_sequence<>{})};
+            (void)product;
+        }
+    }
+
+    auto test_basic_operation() -> void
+    {
+        test_detail::basic_operation op{sender0{}, receiver{}};
+        (void)op;
+        //-dk:TODO test basic_operation
+    }
 }
 
 auto main() -> int
@@ -767,4 +809,6 @@ auto main() -> int
     test_env_type();
     test_basic_receiver<int>();
     test_completion_tag();
+    test_connect_all();
+    test_basic_operation();
 }

src/beman/execution26/tests/execution-syn.pass.cpp

@@ -1,6 +1,8 @@
 // src/beman/execution26/tests/execution-syn.pass.cpp                 -*-C++-*-
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 
+#include <beman/execution26/detail/connect_result_t.hpp>
+#include <beman/execution26/detail/connect.hpp>
 #include <beman/execution26/detail/single_sender.hpp>
 #include <beman/execution26/detail/single_sender_value_type.hpp>
 #include <beman/execution26/detail/type_list.hpp>
@@ -320,6 +322,45 @@ namespace
         static_assert(test_detail::single_sender<multi_type_sender, test_std::empty_env>);
         static_assert(not test_detail::single_sender<no_value_sender, test_std::empty_env>);
     }
+
+    struct connect_sender
+    {
+        using sender_concept = test_std::sender_t;
+        template <typename Receiver>
+        struct state
+        {
+            using operation_state_concept = test_std::operation_state_t;
+            auto start() noexcept -> void {}
+        };
+        struct tag {};
+
+        tag t{};
+        int d{};
+
+        template <test_std::receiver Receiver>
+        auto connect(Receiver&&) const noexcept -> state<Receiver>
+        {
+            return {};
+        }
+    };
+
+    auto test_conect_result_t() -> void
+    {
+        struct receiver
+        {
+            using receiver_concept = test_std::receiver_t;
+        };
+
+        static_assert(test_std::sender<connect_sender>);
+        static_assert(test_std::receiver<receiver>);
+        static_assert(requires{ connect_sender{}.connect(receiver{}); });
+
+        auto op{test_std::connect(connect_sender{}, receiver{})};
+        static_assert(std::same_as<
+            decltype(op),
+            test_std::connect_result_t<connect_sender, receiver>
+        >);
+    }
 }
 
 auto main() -> int
@@ -332,4 +373,5 @@ auto main() -> int
     test_type_list();
     test_single_sender_value_type();
     test_single_sender();
+    test_conect_result_t();
 }