Implement P3826 - fix sender customization

Makefile

@@ -134,6 +134,23 @@ doc:
 	./bin/mk-doc.py docs/*.mds
 	doxygen docs/Doxyfile
 
+LLVM_VERSION=22.1.0
+DEV_DIR=build/dev-$(shell uname -s)
+TESTCASE = *
+DEV_TEST_OPTION=-DBEMAN_EXECUTION_TEST_CASE=$(TESTCASE)
+
+dev-config:
+	PATH=/opt/llvm-$(LLVM_VERSION)/bin:$$PATH CXX=clang++ cmake -B $(DEV_DIR) -G Ninja -DBEMAN_EXECUTION_BUILD_EXAMPLES=OFF -DBEMAN_EXECUTION_INSTALL_CONFIG_FILE_PACKAGE=OFF $(DEV_TEST_OPTION)
+
+dev-build: dev-config
+	PATH=/opt/llvm-$(LLVM_VERSION)/bin:$$PATH CXX=clang++ cmake --build $(DEV_DIR)
+
+dev-test: dev-build
+	PATH=/opt/llvm-$(LLVM_VERSION)/bin:$$PATH CXX=clang++ ctest --test-dir $(DEV_DIR) -R beman.execution.$(TESTCASE).test
+
+dev: dev-test
+
+
 # $(SANITIZERS):
 # 	$(MAKE) SANITIZER=$@
 

include/beman/execution/detail/affine_on.hpp

@@ -17,11 +17,11 @@ import std;
 import beman.execution.detail.basic_sender;
 import beman.execution.detail.completion_signatures;
 import beman.execution.detail.completion_signatures_of_t;
+import beman.execution.detail.continues_on;
 import beman.execution.detail.env;
 import beman.execution.detail.forward_like;
 import beman.execution.detail.fwd_env;
 import beman.execution.detail.get_completion_signatures;
-import beman.execution.detail.get_domain_early;
 import beman.execution.detail.get_scheduler;
 import beman.execution.detail.get_stop_token;
 import beman.execution.detail.make_sender;
@@ -38,20 +38,19 @@ import beman.execution.detail.sender_has_affine_on;
 import beman.execution.detail.set_value;
 import beman.execution.detail.store_receiver;
 import beman.execution.detail.tag_of_t;
-import beman.execution.detail.transform_sender;
 import beman.execution.detail.unstoppable;
 import beman.execution.detail.write_env;
 #else
+#include <beman/execution/detail/completion_signatures_of_t.hpp>
+#include <beman/execution/detail/continues_on.hpp>
 #include <beman/execution/detail/env.hpp>
 #include <beman/execution/detail/forward_like.hpp>
 #include <beman/execution/detail/fwd_env.hpp>
-#include <beman/execution/detail/get_domain_early.hpp>
 #include <beman/execution/detail/get_scheduler.hpp>
 #include <beman/execution/detail/get_stop_token.hpp>
 #include <beman/execution/detail/make_sender.hpp>
 #include <beman/execution/detail/never_stop_token.hpp>
 #include <beman/execution/detail/prop.hpp>
-#include <beman/execution/detail/schedule_from.hpp>
 #include <beman/execution/detail/scheduler.hpp>
 #include <beman/execution/detail/sender.hpp>
 #include <beman/execution/detail/sender_adaptor_closure.hpp>
@@ -60,7 +59,6 @@ import beman.execution.detail.write_env;
 #include <beman/execution/detail/set_value.hpp>
 #include <beman/execution/detail/store_receiver.hpp>
 #include <beman/execution/detail/tag_of_t.hpp>
-#include <beman/execution/detail/transform_sender.hpp>
 #include <beman/execution/detail/unstoppable.hpp>
 #include <beman/execution/detail/write_env.hpp>
 #endif
@@ -100,10 +98,8 @@ struct affine_on_t : ::beman::execution::sender_adaptor_closure<affine_on_t> {
      */
     template <::beman::execution::sender Sender>
     auto operator()(Sender&& sender) const {
-        return ::beman::execution::transform_sender(
-            ::beman::execution::detail::get_domain_early(sender),
-            ::beman::execution::detail::make_sender(
-                *this, ::beman::execution::env<>{}, ::std::forward<Sender>(sender)));
+        return ::beman::execution::detail::make_sender(
+            *this, ::beman::execution::env<>{}, ::std::forward<Sender>(sender));
     }
 
     /**
@@ -136,7 +132,7 @@ struct affine_on_t : ::beman::execution::sender_adaptor_closure<affine_on_t> {
             { ::beman::execution::get_scheduler(env) } -> ::beman::execution::scheduler;
             { ::beman::execution::schedule(::beman::execution::get_scheduler(env)) } -> ::beman::execution::sender;
         }
-    static auto transform_sender(Sender&& sender, const Env& ev) {
+    static auto transform_sender(::beman::execution::set_value_t, Sender&& sender, const Env& ev) {
         static_assert(requires {
             {
                 ::beman::execution::get_completion_signatures<decltype(::beman::execution::unstoppable(
@@ -158,9 +154,9 @@ struct affine_on_t : ::beman::execution::sender_adaptor_closure<affine_on_t> {
             return ::beman::execution::detail::store_receiver(
                 ::beman::execution::detail::forward_like<Sender>(child),
                 []<typename Child>(Child&& child, const auto& ev) {
-                    return ::beman::execution::unstoppable(::beman::execution::schedule_from(
-                        ::beman::execution::get_scheduler(ev),
-                        ::beman::execution::write_env(::std::forward<Child>(child), ev)));
+                    return ::beman::execution::unstoppable(::beman::execution::continues_on(
+                        ::beman::execution::write_env(::std::forward<Child>(child), ev),
+                        ::beman::execution::get_scheduler(ev)));
                 });
         }
     }

include/beman/execution/detail/associate.hpp

@@ -22,7 +22,6 @@ import beman.execution.detail.completion_signatures_for;
 import beman.execution.detail.default_impls;
 import beman.execution.detail.env;
 import beman.execution.detail.forward_like;
-import beman.execution.detail.get_domain_early;
 import beman.execution.detail.impls_for;
 import beman.execution.detail.make_sender;
 import beman.execution.detail.nothrow_callable;
@@ -32,19 +31,16 @@ import beman.execution.detail.sender_adaptor_closure;
 import beman.execution.detail.set_stopped;
 import beman.execution.detail.set_value;
 import beman.execution.detail.start;
-import beman.execution.detail.transform_sender;
 import beman.execution.detail.valid_completion_signatures;
 #else
 #include <beman/execution/detail/connect.hpp>
 #include <beman/execution/detail/default_impls.hpp>
-#include <beman/execution/detail/get_domain_early.hpp>
 #include <beman/execution/detail/impls_for.hpp>
 #include <beman/execution/detail/make_sender.hpp>
 #include <beman/execution/detail/nothrow_callable.hpp>
 #include <beman/execution/detail/scope_token.hpp>
 #include <beman/execution/detail/sender.hpp>
 #include <beman/execution/detail/sender_adaptor.hpp>
-#include <beman/execution/detail/transform_sender.hpp>
 #endif
 
 // ----------------------------------------------------------------------------
@@ -108,12 +104,8 @@ associate_data(Token, Sender&&) -> associate_data<Token, Sender>;
 struct associate_t {
     template <::beman::execution::sender Sender, ::beman::execution::scope_token Token>
     auto operator()(Sender&& sender, Token token) const {
-        auto domain(::beman::execution::detail::get_domain_early(sender));
-        return ::beman::execution::transform_sender(
-            domain,
-            ::beman::execution::detail::make_sender(
-                *this,
-                ::beman::execution::detail::associate_data(::std::move(token), ::std::forward<Sender>(sender))));
+        return ::beman::execution::detail::make_sender(
+            *this, ::beman::execution::detail::associate_data(::std::move(token), ::std::forward<Sender>(sender)));
     }
 
     template <::beman::execution::scope_token Token>

include/beman/execution/detail/atomic_intrusive_stack.hpp

@@ -80,11 +80,9 @@ class atomic_intrusive_stack<Next> {
         auto  stack = ::beman::execution::detail::intrusive_stack<Next>{};
         void* ptr   = head_.exchange(this);
         if (ptr == this) {
-            return stack;
+            return {};
         }
-        auto item   = static_cast<Item*>(ptr);
-        stack.head_ = item;
-        return stack;
+        return ::beman::execution::detail::intrusive_stack<Next>{static_cast<Item*>(ptr)};
     }
 
   private:

include/beman/execution/detail/basic_receiver.hpp

@@ -72,7 +72,7 @@ template <typename Sender, typename Receiver, typename Index>
         this->complete(Index(),
                        this->op->state,
                        this->op->receiver,
-                       ::beman::execution::set_value_t(),
+                       ::beman::execution::set_value,
                        ::std::forward<Args>(args)...);
     }
 
@@ -81,11 +81,8 @@ template <typename Sender, typename Receiver, typename Index>
         requires ::beman::execution::detail::
             callable<decltype(complete), Index, state_t&, Receiver&, ::beman::execution::set_error_t, Error>
     {
-        this->complete(Index(),
-                       this->op->state,
-                       this->op->receiver,
-                       ::beman::execution::set_error_t(),
-                       ::std::forward<Error>(error));
+        this->complete(
+            Index(), this->op->state, this->op->receiver, ::beman::execution::set_error, ::std::forward<Error>(error));
     }
 
     auto set_stopped() && noexcept -> void

include/beman/execution/detail/bulk.hpp

@@ -21,7 +21,6 @@ import beman.execution.detail.completion_signatures_of_t;
 import beman.execution.detail.default_impls;
 import beman.execution.detail.execution_policy;
 import beman.execution.detail.forward_like;
-import beman.execution.detail.get_domain_early;
 import beman.execution.detail.make_sender;
 import beman.execution.detail.meta.combine;
 import beman.execution.detail.meta.unique;
@@ -31,15 +30,13 @@ import beman.execution.detail.sender_adaptor_closure;
 import beman.execution.detail.sender_for;
 import beman.execution.detail.set_error;
 import beman.execution.detail.set_value;
-import beman.execution.detail.transform_sender;
 #else
 #include <beman/execution/detail/basic_sender.hpp>
 #include <beman/execution/detail/completion_signatures.hpp>
 #include <beman/execution/detail/completion_signatures_of_t.hpp>
 #include <beman/execution/detail/default_impls.hpp>
 #include <beman/execution/detail/execution_policy.hpp>
 #include <beman/execution/detail/forward_like.hpp>
-#include <beman/execution/detail/get_domain_early.hpp>
 #include <beman/execution/detail/make_sender.hpp>
 #include <beman/execution/detail/meta_combine.hpp>
 #include <beman/execution/detail/meta_unique.hpp>
@@ -49,7 +46,6 @@ import beman.execution.detail.transform_sender;
 #include <beman/execution/detail/sender_for.hpp>
 #include <beman/execution/detail/set_error.hpp>
 #include <beman/execution/detail/set_value.hpp>
-#include <beman/execution/detail/transform_sender.hpp>
 #endif
 
 // ----------------------------------------------------------------------------
@@ -120,13 +116,11 @@ struct bulk_algo_t : ::beman::execution::sender_adaptor_closure<bulk_algo_t<IsCh
                  ::beman::execution::is_execution_policy_v<::std::remove_cvref_t<Policy>> && ::std::integral<Shape> &&
                  ::std::copy_constructible<::std::decay_t<F>>)
     auto operator()(Sender&& sndr, Policy&& policy, Shape shape, F&& f) const {
-        return ::beman::execution::transform_sender(
-            ::beman::execution::detail::get_domain_early(sndr),
-            ::beman::execution::detail::make_sender(
-                *this,
-                ::beman::execution::detail::product_type<::std::remove_cvref_t<Policy>, Shape, ::std::decay_t<F>>{
-                    ::std::forward<Policy>(policy), shape, ::std::forward<F>(f)},
-                ::std::forward<Sender>(sndr)));
+        return ::beman::execution::detail::make_sender(
+            *this,
+            ::beman::execution::detail::product_type<::std::remove_cvref_t<Policy>, Shape, ::std::decay_t<F>>{
+                ::std::forward<Policy>(policy), shape, ::std::forward<F>(f)},
+            ::std::forward<Sender>(sndr));
     }
 
   private:
@@ -210,17 +204,15 @@ struct bulk_t : ::beman::execution::sender_adaptor_closure<bulk_t> {
                  ::beman::execution::is_execution_policy_v<::std::remove_cvref_t<Policy>> && ::std::integral<Shape> &&
                  ::std::copy_constructible<::std::decay_t<F>>)
     auto operator()(Sender&& sndr, Policy&& policy, Shape shape, F&& f) const {
-        return ::beman::execution::transform_sender(
-            ::beman::execution::detail::get_domain_early(sndr),
-            ::beman::execution::detail::make_sender(
-                *this,
-                ::beman::execution::detail::product_type<::std::remove_cvref_t<Policy>, Shape, ::std::decay_t<F>>{
-                    ::std::forward<Policy>(policy), shape, ::std::forward<F>(f)},
-                ::std::forward<Sender>(sndr)));
+        return ::beman::execution::detail::make_sender(
+            *this,
+            ::beman::execution::detail::product_type<::std::remove_cvref_t<Policy>, Shape, ::std::decay_t<F>>{
+                ::std::forward<Policy>(policy), shape, ::std::forward<F>(f)},
+            ::std::forward<Sender>(sndr));
     }
 
-    template <::beman::execution::detail::sender_for<bulk_t> Sender, typename... Env>
-    auto transform_sender(Sender&& sndr, Env&&...) const {
+    template <::beman::execution::detail::sender_for<bulk_t> Sender, typename Env>
+    auto transform_sender(::beman::execution::set_value_t, Sender&& sndr, const Env&) const {
         auto data  = ::beman::execution::detail::forward_like<Sender>(sndr.template get<1>());
         auto child = ::beman::execution::detail::forward_like<Sender>(sndr.template get<2>());
 

include/beman/execution/detail/common_domain.hpp

@@ -0,0 +1,47 @@
+// include/beman/execution/detail/common_domain.hpp                  -*-C++-*-
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+
+#ifndef INCLUDED_BEMAN_EXECUTION_DETAIL_COMMON_DOMAIN
+#define INCLUDED_BEMAN_EXECUTION_DETAIL_COMMON_DOMAIN
+
+#include <beman/execution/detail/common.hpp>
+#ifdef BEMAN_HAS_IMPORT_STD
+import std;
+#else
+#include <concepts>
+#include <type_traits>
+#endif
+#ifdef BEMAN_HAS_MODULES
+import beman.execution.detail.indeterminate_domain;
+#else
+#include <beman/execution/detail/indeterminate_domain.hpp>
+#endif
+
+// ----------------------------------------------------------------------------
+
+namespace beman::execution::detail {
+
+template <typename... Domains>
+struct common_domain_impl {
+    using type = ::beman::execution::indeterminate_domain<Domains...>;
+};
+
+template <typename... Domains>
+    requires requires { typename ::std::common_type_t<Domains...>; }
+struct common_domain_impl<Domains...> {
+    using type = ::std::common_type_t<Domains...>;
+};
+
+template <typename... Domains>
+using common_domain_t = typename common_domain_impl<::std::decay_t<Domains>...>::type;
+
+template <typename... Domains>
+constexpr auto common_domain(Domains&&...) noexcept {
+    return common_domain_t<Domains...>{};
+}
+
+} // namespace beman::execution::detail
+
+// ----------------------------------------------------------------------------
+
+#endif // INCLUDED_BEMAN_EXECUTION_DETAIL_COMMON_DOMAIN

include/beman/execution/detail/compl_domain.hpp

@@ -0,0 +1,44 @@
+// include/beman/execution/detail/compl_domain.hpp             -*-C++-*-
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+
+#ifndef INCLUDED_BEMAN_EXECUTION_DETAIL_COMPL_DOMAIN
+#define INCLUDED_BEMAN_EXECUTION_DETAIL_COMPL_DOMAIN
+
+#include <beman/execution/detail/common.hpp>
+#ifdef BEMAN_HAS_IMPORT_STD
+import std;
+#else
+#include <type_traits>
+#endif
+#ifdef BEMAN_HAS_MODULES
+import beman.execution.detail.default_domain;
+import beman.execution.detail.get_completion_domain;
+import beman.execution.detail.get_env;
+#else
+#include <beman/execution/detail/default_domain.hpp>
+#include <beman/execution/detail/get_completion_domain.hpp>
+#include <beman/execution/detail/get_env.hpp>
+#endif
+
+// ----------------------------------------------------------------------------
+
+namespace beman::execution::detail {
+template <typename Tag = void, typename Sndr, typename... Envs>
+constexpr auto compl_domain(const Sndr& sndr, const Envs&... envs) noexcept {
+    if constexpr (requires {
+                      ::beman::execution::get_completion_domain<Tag>(::beman::execution::get_env(sndr), envs...);
+                  }) {
+        return ::beman::execution::get_completion_domain<Tag>(::beman::execution::get_env(sndr), envs...);
+    } else {
+        return ::beman::execution::default_domain();
+    }
+}
+
+template <typename Tag, typename Sndr, typename... Envs>
+using compl_domain_of_t =
+    decltype(::beman::execution::detail::compl_domain<Tag>(::std::declval<Sndr>(), ::std::declval<const Envs&>()...));
+} // namespace beman::execution::detail
+
+// ----------------------------------------------------------------------------
+
+#endif // INCLUDED_BEMAN_EXECUTION_DETAIL_COMPL_DOMAIN