From 3b9b901df79a27347c920fa155adf85b26543a61 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Dietmar=20K=C3=BChl?= <dietmar.kuehl@me.com>
Date: Fri, 30 Aug 2024 20:21:09 +0100
Subject: [PATCH 1/5] added get_domain_early

---
 .../execution26/detail/get_domain_early.hpp   | 40 +++++++++++++
 .../execution26/tests/exec-snd-expos.pass.cpp | 59 ++++++++++++++++++-
 2 files changed, 98 insertions(+), 1 deletion(-)
 create mode 100644 include/beman/execution26/detail/get_domain_early.hpp

diff --git a/include/beman/execution26/detail/get_domain_early.hpp b/include/beman/execution26/detail/get_domain_early.hpp
new file mode 100644
index 00000000..2ea79d5a
--- /dev/null
+++ b/include/beman/execution26/detail/get_domain_early.hpp
@@ -0,0 +1,40 @@
+// include/beman/execution26/detail/get_domain_early.hpp              -*-C++-*-
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+
+#ifndef INCLUDED_BEMAN_EXECUTION26_DETAIL_GET_DOMAIN_EARLY
+#define INCLUDED_BEMAN_EXECUTION26_DETAIL_GET_DOMAIN_EARLY
+
+#include <beman/execution26/detail/completion_domain.hpp>
+#include <beman/execution26/detail/default_domain.hpp>
+#include <beman/execution26/detail/get_domain.hpp>
+#include <beman/execution26/detail/get_env.hpp>
+
+// ----------------------------------------------------------------------------
+
+namespace beman::execution26::detail
+{
+    template <typename Sender>
+    constexpr auto get_domain_early(Sender const& sender) noexcept
+    {
+        if constexpr (requires{
+                ::beman::execution26::get_domain(
+                    ::beman::execution26::get_env(sender)
+                );
+            })
+            return decltype(
+                ::beman::execution26::get_domain(
+                    ::beman::execution26::get_env(sender)
+                )
+            ){};
+        else if constexpr (requires{
+                ::beman::execution26::detail::completion_domain(sender);
+            })
+            return decltype(::beman::execution26::detail::completion_domain(sender)){};
+        else
+            return ::beman::execution26::default_domain{};
+    }
+}
+
+// ----------------------------------------------------------------------------
+
+#endif
diff --git a/src/beman/execution26/tests/exec-snd-expos.pass.cpp b/src/beman/execution26/tests/exec-snd-expos.pass.cpp
index cc8dc265..fc432ec1 100644
--- a/src/beman/execution26/tests/exec-snd-expos.pass.cpp
+++ b/src/beman/execution26/tests/exec-snd-expos.pass.cpp
@@ -15,6 +15,7 @@
 #include <beman/execution26/detail/sched_env.hpp>
 #include <beman/execution26/detail/sender.hpp>
 #include <beman/execution26/detail/query_with_default.hpp>
+#include <beman/execution26/detail/get_domain_early.hpp>
 #include <beman/execution26/detail/get_domain_late.hpp>
 #include <beman/execution26/detail/default_impls.hpp>
 #include <beman/execution26/detail/impls_for.hpp>
@@ -332,6 +333,17 @@ namespace
             auto operator== (scheduler const&) const -> bool = default;
         };
 
+        template <>
+        struct env<domain>
+        {
+            template <typename Tag>
+            auto query(test_std::get_completion_scheduler_t<Tag> const&) const noexcept
+                -> scheduler<domain>
+            {
+                return {};
+            }
+        };
+
         template <>
         struct env<common>
         {
@@ -407,8 +419,52 @@ namespace
         assert(result2.default_value == 74);
     }
 
+    auto test_get_domain_early() -> void
+    {
+        struct plain_sender
+        {
+            using sender_concept = test_std::sender_t;
+        };
+        static_assert(test_std::sender<plain_sender>);
+        static_assert(std::same_as<
+            test_std::default_domain,
+            decltype(test_detail::get_domain_early(plain_sender{}))
+        >);
+
+        namespace cd = completion_domain;
+        static_assert(test_std::sender<cd::sender<cd::domain>>);
+        static_assert(std::same_as<
+            cd::domain,
+            decltype(test_detail::get_domain_early(cd::sender<cd::domain>{}))
+        >);
+
+        struct sender_with_domain
+        {
+            using sender_concept = test_std::sender_t;
+            struct domain {};
+            struct env
+            {
+                auto query(test_std::get_domain_t const&) const noexcept -> domain { return {}; }
+            };
+            auto get_env() const noexcept -> env { return {}; }
+        };
+        static_assert(test_std::sender<sender_with_domain>);
+        static_assert(std::same_as<
+            sender_with_domain::env,
+            decltype(test_std::get_env(sender_with_domain{}))
+        >);
+        static_assert(std::same_as<
+            sender_with_domain::domain,
+            decltype(test_std::get_domain(sender_with_domain::env{}))
+        >);
+        static_assert(std::same_as<
+            sender_with_domain::domain,
+            decltype(test_detail::get_domain_early(sender_with_domain{}))
+        >);
+    }
+
     template <typename Expect>
-    auto test_get_domain_late(auto sender, auto env)
+    auto test_get_domain_late(auto sender, auto env) -> void
     {
         static_assert(test_std::sender<decltype(sender)>);
         static_assert(test_detail::queryable<decltype(env)>);
@@ -1186,6 +1242,7 @@ auto main() -> int
     test_sched_env();
     test_completion_domain();
     test_query_with_default();
+    test_get_domain_early();
     test_get_domain_late();
     test_default_impls();
     test_impls_for();

From ea62dbfafd47997811bf57ccfbcabde61d6b6369 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Dietmar=20K=C3=BChl?= <dietmar.kuehl@me.com>
Date: Sat, 31 Aug 2024 01:03:35 +0100
Subject: [PATCH 2/5] added make_sender

---
 .../beman/execution26/detail/make_sender.hpp  | 35 +++++++++++++++++++
 .../execution26/tests/exec-snd-expos.pass.cpp | 27 ++++++++++++++
 2 files changed, 62 insertions(+)
 create mode 100644 include/beman/execution26/detail/make_sender.hpp

diff --git a/include/beman/execution26/detail/make_sender.hpp b/include/beman/execution26/detail/make_sender.hpp
new file mode 100644
index 00000000..d3394ab6
--- /dev/null
+++ b/include/beman/execution26/detail/make_sender.hpp
@@ -0,0 +1,35 @@
+// include/beman/execution26/detail/make_sender.hpp                   -*-C++-*-
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+
+#ifndef INCLUDED_BEMAN_EXECUTION26_DETAIL_MAKE_SENDER
+#define INCLUDED_BEMAN_EXECUTION26_DETAIL_MAKE_SENDER
+
+#include <beman/execution26/detail/basic_sender.hpp>
+#include <beman/execution26/detail/movable_value.hpp>
+#include <beman/execution26/detail/sender.hpp>
+#include <concepts>
+#include <type_traits>
+
+// ----------------------------------------------------------------------------
+
+namespace beman::execution26::detail
+{
+    struct make_sender_empty {};
+
+    template <typename Tag,
+              typename Data = ::beman::execution26::detail::make_sender_empty,
+              typename... Child>
+        requires ::std::semiregular<Tag>
+        && ::beman::execution26::detail::movable_value<Data>
+        && (::beman::execution26::sender<Child> && ...)
+    constexpr auto make_sender(Tag tag, Data&& data, Child&&... child)
+    {
+        return ::beman::execution26::detail::basic_sender<
+            Tag, ::std::decay_t<Data>, ::std::decay_t<Child>...
+            >{tag, ::std::forward<Data>(data), child...};
+    }
+}
+
+// ----------------------------------------------------------------------------
+
+#endif
diff --git a/src/beman/execution26/tests/exec-snd-expos.pass.cpp b/src/beman/execution26/tests/exec-snd-expos.pass.cpp
index fc432ec1..f513a058 100644
--- a/src/beman/execution26/tests/exec-snd-expos.pass.cpp
+++ b/src/beman/execution26/tests/exec-snd-expos.pass.cpp
@@ -1,6 +1,7 @@
 // src/beman/execution26/tests/exe-snd-expos.pass.cpp                 -*-C++-*-
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 
+#include <beman/execution26/detail/make_sender.hpp>
 #include <beman/execution26/detail/basic_sender.hpp>
 #include <beman/execution26/detail/completion_signatures_for.hpp>
 #include <beman/execution26/detail/connect_all_result.hpp>
@@ -1231,6 +1232,31 @@ namespace
             basic_sender::indices_for
         >);
     }
+
+    template <typename T>
+    auto test_make_sender() -> void
+    {
+        {
+            auto sender{test_detail::make_sender(tag{}, {})};
+            static_assert(test_std::sender<decltype(sender)>);
+        }
+        {
+            auto sender{test_detail::make_sender(tag{}, int{17})};
+            static_assert(test_std::sender<decltype(sender)>);
+            static_assert(std::same_as<test_detail::basic_sender<tag, int>, decltype(sender)>);
+        }
+        {
+            static_assert(not requires{ test_detail::make_sender(tag{}, int{17}, T()); });
+        }
+        {
+            auto sender{test_detail::make_sender(tag{}, int{17}, sender0{})};
+            static_assert(test_std::sender<decltype(sender)>);
+            static_assert(std::same_as<
+                test_detail::basic_sender<tag, int, sender0>,
+                decltype(sender)
+            >);
+        }
+    }
 }
 
 auto main() -> int
@@ -1259,4 +1285,5 @@ auto main() -> int
     test_basic_operation();
     test_completion_signatures_for();
     test_basic_sender();
+    test_make_sender<int>();
 }
\ No newline at end of file

From e9fd69c369d29aca0f609136ff386f929fa4aaae Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Dietmar=20K=C3=BChl?= <dietmar.kuehl@me.com>
Date: Sat, 31 Aug 2024 01:44:30 +0100
Subject: [PATCH 3/5] added sender_adaptor_closure

---
 .../detail/sender_adaptor_closure.hpp         | 44 +++++++++++++++++++
 .../execution26/tests/exec-snd-expos.pass.cpp |  1 +
 .../execution26/tests/execution-syn.pass.cpp  | 39 ++++++++++++++++
 3 files changed, 84 insertions(+)
 create mode 100644 include/beman/execution26/detail/sender_adaptor_closure.hpp

diff --git a/include/beman/execution26/detail/sender_adaptor_closure.hpp b/include/beman/execution26/detail/sender_adaptor_closure.hpp
new file mode 100644
index 00000000..be52c9ba
--- /dev/null
+++ b/include/beman/execution26/detail/sender_adaptor_closure.hpp
@@ -0,0 +1,44 @@
+// include/beman/execution26/detail/sender_adaptor_closure.hpp        -*-C++-*-
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+
+#ifndef INCLUDED_BEMAN_EXECUTION26_DETAIL_SENDER_ADAPTOR_CLOSURE
+#define INCLUDED_BEMAN_EXECUTION26_DETAIL_SENDER_ADAPTOR_CLOSURE
+
+#include <beman/execution26/detail/sender.hpp>
+#include <concepts>
+#include <utility>
+
+// ----------------------------------------------------------------------------
+
+namespace beman::execution26::detail::pipeable
+{
+    struct sender_adaptor_closure_base {};
+}
+
+namespace beman::execution26
+{
+    template <typename>
+    struct sender_adaptor_closure
+        : ::beman::execution26::detail::pipeable::sender_adaptor_closure_base
+    {
+    };
+}
+
+namespace beman::execution26::detail::pipeable
+{
+    template <::beman::execution26::sender Sender, typename Adaptor>
+        requires (not ::beman::execution26::sender<Adaptor>)
+        && ::std::derived_from<Adaptor, ::beman::execution26::sender_adaptor_closure<Adaptor>>
+        && requires(Sender&& sender, Adaptor const& adaptor)
+        {
+            { adaptor(::std::forward<Sender>(sender)) } -> ::beman::execution26::sender;
+        }
+    auto operator| (Sender&& sender, Adaptor const& adaptor)
+    {
+        return adaptor(::std::forward<Sender>(sender));
+    }
+}
+
+// ----------------------------------------------------------------------------
+
+#endif
diff --git a/src/beman/execution26/tests/exec-snd-expos.pass.cpp b/src/beman/execution26/tests/exec-snd-expos.pass.cpp
index f513a058..7f402fb8 100644
--- a/src/beman/execution26/tests/exec-snd-expos.pass.cpp
+++ b/src/beman/execution26/tests/exec-snd-expos.pass.cpp
@@ -508,6 +508,7 @@ namespace
         {
             using sender_concept = test_std::sender_t;
         };
+        static_assert(test_std::sender<no_domain_sender>);
         test_get_domain_late<test_std::default_domain>(no_domain_sender{}, test_std::empty_env{});
 
         struct scheduler_env
diff --git a/src/beman/execution26/tests/execution-syn.pass.cpp b/src/beman/execution26/tests/execution-syn.pass.cpp
index cce6850a..31ef5529 100644
--- a/src/beman/execution26/tests/execution-syn.pass.cpp
+++ b/src/beman/execution26/tests/execution-syn.pass.cpp
@@ -1,6 +1,7 @@
 // src/beman/execution26/tests/execution-syn.pass.cpp                 -*-C++-*-
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 
+#include <beman/execution26/detail/sender_adaptor_closure.hpp>
 #include <beman/execution26/detail/decays_to.hpp>
 #include <beman/execution26/detail/connect_result_t.hpp>
 #include <beman/execution26/detail/connect.hpp>
@@ -20,6 +21,7 @@
 
 namespace
 {
+    auto use(auto&&) -> void {}
     struct scheduler
     {
         struct env
@@ -377,6 +379,42 @@ namespace
         static_assert(not test_detail::decays_to<type, type&>);
         static_assert(not test_detail::decays_to<other, type>);
     }
+
+    template <test_std::sender>
+    struct adapted_sender
+    {
+        using sender_concept = test_std::sender_t;
+    };
+
+    struct closure_t
+        : test_std::sender_adaptor_closure<closure_t>
+    {
+        template <test_std::sender Sender>
+        auto operator()(Sender&&) const -> adapted_sender<Sender>
+        {
+            return {};
+        }
+    };
+    constexpr closure_t closure{};
+
+    auto test_sender_adaptor_closure() -> void
+    {
+        use(test_std::sender_adaptor_closure<int>{});
+        struct sender
+        {
+            using sender_concept = test_std::sender_t;
+        };
+        static_assert(test_std::sender<sender>);
+
+        static_assert(test_std::sender<adapted_sender<sender>>);
+        static_assert(not test_std::sender<closure_t>);
+
+        auto direct{closure(sender{})};
+        static_assert(std::same_as<adapted_sender<sender>, decltype(direct)>);
+        auto via_op{sender{} | closure };
+        use(via_op);
+        static_assert(std::same_as<adapted_sender<sender>, decltype(via_op)>);
+    }
 }
 
 auto main() -> int
@@ -391,4 +429,5 @@ auto main() -> int
     test_single_sender();
     test_conect_result_t();
     test_decays_to();
+    test_sender_adaptor_closure();
 }

From 3d8f1478c7a5686bdfeff49673a0eefff943ee8c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Dietmar=20K=C3=BChl?= <dietmar.kuehl@me.com>
Date: Sat, 31 Aug 2024 02:26:39 +0100
Subject: [PATCH 4/5] added sender_adaptor

---
 .../execution26/detail/sender_adaptor.hpp     | 61 +++++++++++++++++++
 .../detail/sender_adaptor_closure.hpp         |  8 ++-
 .../execution26/tests/execution-syn.pass.cpp  | 34 ++++++++++-
 3 files changed, 99 insertions(+), 4 deletions(-)
 create mode 100644 include/beman/execution26/detail/sender_adaptor.hpp

diff --git a/include/beman/execution26/detail/sender_adaptor.hpp b/include/beman/execution26/detail/sender_adaptor.hpp
new file mode 100644
index 00000000..0572b814
--- /dev/null
+++ b/include/beman/execution26/detail/sender_adaptor.hpp
@@ -0,0 +1,61 @@
+// include/beman/execution26/detail/sender_adaptor.hpp                -*-C++-*-
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+
+#ifndef INCLUDED_BEMAN_EXECUTION26_DETAIL_SENDER_ADAPTOR
+#define INCLUDED_BEMAN_EXECUTION26_DETAIL_SENDER_ADAPTOR
+
+#include <beman/execution26/detail/sender.hpp>
+#include <beman/execution26/detail/sender_adaptor_closure.hpp>
+#include <beman/execution26/detail/sender_decompose.hpp>
+#include <beman/execution26/detail/product_type.hpp>
+#include <type_traits>
+#include <utility>
+
+// ----------------------------------------------------------------------------
+
+namespace beman::execution26::detail
+{
+    template <typename Adaptor, typename T0, typename... T>
+    struct sender_adaptor
+        : ::beman::execution26::detail::product_type<
+            ::std::decay_t<Adaptor>, ::std::decay_t<T0>, ::std::decay_t<T>...>
+        , ::beman::execution26::sender_adaptor_closure<sender_adaptor<Adaptor, T0, T...>>
+    {
+        template <::beman::execution26::sender Sender>
+        static auto apply(Sender&& sender, auto&& self)
+        {
+            using base_type = ::beman::execution26::detail::product_type<
+                ::std::decay_t<Adaptor>, ::std::decay_t<T0>, ::std::decay_t<T>...>;
+            static constexpr ::beman::execution26::detail::sender_any_t at{};
+            if constexpr (requires{ base_type{ at, at, at, at }; })
+            {
+                auto&&[adaptor, arg0, arg1, arg2] = self;
+                return adaptor(::std::forward<Sender>(sender), arg0, arg1, arg2);
+            }
+            if constexpr (requires{ base_type{ at, at, at }; })
+            {
+                auto&&[adaptor, arg0, arg1] = self;
+                return adaptor(::std::forward<Sender>(sender), arg0, arg1);
+            }
+            else if constexpr (requires{ base_type{ at, at }; })
+            {
+                auto&&[adaptor, arg0] = self;
+                return adaptor(::std::forward<Sender>(sender), arg0);
+            }
+        }
+        template <::beman::execution26::sender Sender>
+        auto operator()(Sender&& sender)
+        {
+            return apply(::std::forward<Sender>(sender), *this);
+        }
+        template <::beman::execution26::sender Sender>
+        auto operator()(Sender&& sender) const
+        {
+            return apply(::std::forward<Sender>(sender), *this);
+        }
+    };
+}
+
+// ----------------------------------------------------------------------------
+
+#endif
diff --git a/include/beman/execution26/detail/sender_adaptor_closure.hpp b/include/beman/execution26/detail/sender_adaptor_closure.hpp
index be52c9ba..6eb64cb9 100644
--- a/include/beman/execution26/detail/sender_adaptor_closure.hpp
+++ b/include/beman/execution26/detail/sender_adaptor_closure.hpp
@@ -6,6 +6,7 @@
 
 #include <beman/execution26/detail/sender.hpp>
 #include <concepts>
+#include <type_traits>
 #include <utility>
 
 // ----------------------------------------------------------------------------
@@ -28,12 +29,13 @@ namespace beman::execution26::detail::pipeable
 {
     template <::beman::execution26::sender Sender, typename Adaptor>
         requires (not ::beman::execution26::sender<Adaptor>)
-        && ::std::derived_from<Adaptor, ::beman::execution26::sender_adaptor_closure<Adaptor>>
-        && requires(Sender&& sender, Adaptor const& adaptor)
+        && ::std::derived_from<::std::decay_t<Adaptor>,
+            ::beman::execution26::sender_adaptor_closure<::std::decay_t<Adaptor>>>
+        && requires(Sender&& sender, Adaptor&& adaptor)
         {
             { adaptor(::std::forward<Sender>(sender)) } -> ::beman::execution26::sender;
         }
-    auto operator| (Sender&& sender, Adaptor const& adaptor)
+    auto operator| (Sender&& sender, Adaptor&& adaptor)
     {
         return adaptor(::std::forward<Sender>(sender));
     }
diff --git a/src/beman/execution26/tests/execution-syn.pass.cpp b/src/beman/execution26/tests/execution-syn.pass.cpp
index 31ef5529..7a89d617 100644
--- a/src/beman/execution26/tests/execution-syn.pass.cpp
+++ b/src/beman/execution26/tests/execution-syn.pass.cpp
@@ -1,6 +1,7 @@
 // src/beman/execution26/tests/execution-syn.pass.cpp                 -*-C++-*-
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 
+#include <beman/execution26/detail/sender_adaptor.hpp>
 #include <beman/execution26/detail/sender_adaptor_closure.hpp>
 #include <beman/execution26/detail/decays_to.hpp>
 #include <beman/execution26/detail/connect_result_t.hpp>
@@ -412,7 +413,37 @@ namespace
         auto direct{closure(sender{})};
         static_assert(std::same_as<adapted_sender<sender>, decltype(direct)>);
         auto via_op{sender{} | closure };
-        use(via_op);
+        static_assert(std::same_as<adapted_sender<sender>, decltype(via_op)>);
+    }
+
+    struct arg_closure_t
+    {
+        template <test_std::sender Sender>
+        auto operator()(Sender&&, int) const -> adapted_sender<Sender>
+        {
+            return {};
+        }
+        auto operator()(int value) const
+        {
+            return test_detail::sender_adaptor<arg_closure_t, int>{{*this, value}};
+        }
+    };
+    constexpr arg_closure_t arg_closure{};
+
+    auto test_sender_adaptor() -> void
+    {
+        struct sender
+        {
+            using sender_concept = test_std::sender_t;
+        };
+        static_assert(test_std::sender<sender>);
+
+        auto closure{arg_closure(17)};
+        static_assert(std::same_as<
+            test_detail::sender_adaptor<arg_closure_t, int>, decltype(closure)>);
+        auto direct{closure(sender{})};
+        static_assert(std::same_as<adapted_sender<sender>, decltype(direct)>);
+        auto via_op{sender{} | closure };
         static_assert(std::same_as<adapted_sender<sender>, decltype(via_op)>);
     }
 }
@@ -430,4 +461,5 @@ auto main() -> int
     test_conect_result_t();
     test_decays_to();
     test_sender_adaptor_closure();
+    test_sender_adaptor();
 }

From 221a90d9fe9a563eb516255d1e5ab13303055486 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Dietmar=20K=C3=BChl?= <dietmar.kuehl@me.com>
Date: Sat, 31 Aug 2024 02:28:50 +0100
Subject: [PATCH 5/5] added a direct initializer of the empty base

---
 src/beman/execution26/tests/execution-syn.pass.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/beman/execution26/tests/execution-syn.pass.cpp b/src/beman/execution26/tests/execution-syn.pass.cpp
index 7a89d617..a88a3b99 100644
--- a/src/beman/execution26/tests/execution-syn.pass.cpp
+++ b/src/beman/execution26/tests/execution-syn.pass.cpp
@@ -425,7 +425,7 @@ namespace
         }
         auto operator()(int value) const
         {
-            return test_detail::sender_adaptor<arg_closure_t, int>{{*this, value}};
+            return test_detail::sender_adaptor<arg_closure_t, int>{{*this, value}, {}};
         }
     };
     constexpr arg_closure_t arg_closure{};