Implement get_forward_progress_guarantee

include/beman/execution/detail/get_forward_progress_guarantee.hpp

@@ -0,0 +1,49 @@
+// include/beman/execution/detail/get_forward_progress_guarantee.hpp              -*-C++-*-
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+
+#ifndef INCLUDED_BEMAN_EXECUTION_DETAIL_GET_FORWARD_PROGRESS_GUARANTEE
+#define INCLUDED_BEMAN_EXECUTION_DETAIL_GET_FORWARD_PROGRESS_GUARANTEE
+
+#include <beman/execution/detail/common.hpp>
+#include <beman/execution/detail/suppress_push.hpp>
+#ifdef BEMAN_HAS_IMPORT_STD
+import std;
+#else
+#include <concepts>
+#endif
+#ifdef BEMAN_HAS_MODULES
+import beman.execution.detail.forwarding_query;
+#else
+#include <beman/execution/detail/forwarding_query.hpp>
+#endif
+
+// ----------------------------------------------------------------------------
+
+namespace beman::execution {
+
+enum class forward_progress_guarantee { concurrent, parallel, weakly_parallel };
+
+struct get_forward_progress_guarantee_t {
+    template <typename Object>
+        requires requires(const Object& object, const get_forward_progress_guarantee_t& tag) { object.query(tag); }
+    auto operator()(const Object& object) const noexcept -> forward_progress_guarantee {
+        static_assert(::std::same_as<decltype(object.query(*this)), forward_progress_guarantee>);
+        return object.query(*this);
+    }
+
+    template <typename Object>
+    auto operator()(const Object&) const noexcept -> forward_progress_guarantee {
+        return forward_progress_guarantee::weakly_parallel;
+    }
+
+    static constexpr auto query(const ::beman::execution::forwarding_query_t&) noexcept -> bool { return true; }
+};
+
+inline constexpr get_forward_progress_guarantee_t get_forward_progress_guarantee{};
+} // namespace beman::execution
+
+// ----------------------------------------------------------------------------
+
+#include <beman/execution/detail/suppress_pop.hpp>
+
+#endif // INCLUDED_BEMAN_EXECUTION_DETAIL_GET_FORWARD_PROGRESS_GUARANTEE

include/beman/execution/detail/run_loop.hpp

@@ -19,6 +19,7 @@ import beman.execution.detail.completion_signatures;
 import beman.execution.detail.env;
 import beman.execution.detail.get_completion_scheduler;
 import beman.execution.detail.get_env;
+import beman.execution.detail.get_forward_progress_guarantee;
 import beman.execution.detail.get_stop_token;
 import beman.execution.detail.immovable;
 import beman.execution.detail.operation_state;
@@ -32,6 +33,7 @@ import beman.execution.detail.unstoppable_token;
 #include <beman/execution/detail/completion_signatures.hpp>
 #include <beman/execution/detail/get_completion_scheduler.hpp>
 #include <beman/execution/detail/get_env.hpp>
+#include <beman/execution/detail/get_forward_progress_guarantee.hpp>
 #include <beman/execution/detail/get_stop_token.hpp>
 #include <beman/execution/detail/immovable.hpp>
 #include <beman/execution/detail/operation_state.hpp>
@@ -113,6 +115,11 @@ class run_loop {
 
         auto schedule() noexcept -> sender { return {this->loop}; }
         auto operator==(const scheduler&) const -> bool = default;
+
+        static constexpr auto query(::beman::execution::get_forward_progress_guarantee_t) noexcept
+            -> ::beman::execution::forward_progress_guarantee {
+            return ::beman::execution::forward_progress_guarantee::parallel;
+        }
     };
 
     enum class state : unsigned char { starting, running, finishing };

src/beman/execution/CMakeLists.txt

@@ -89,6 +89,7 @@ target_sources(
                 ${PROJECT_SOURCE_DIR}/include/beman/execution/detail/get_domain_early.hpp
                 ${PROJECT_SOURCE_DIR}/include/beman/execution/detail/get_domain_late.hpp
                 ${PROJECT_SOURCE_DIR}/include/beman/execution/detail/get_env.hpp
+                ${PROJECT_SOURCE_DIR}/include/beman/execution/detail/get_forward_progress_guarantee.hpp
                 ${PROJECT_SOURCE_DIR}/include/beman/execution/detail/get_scheduler.hpp
                 ${PROJECT_SOURCE_DIR}/include/beman/execution/detail/get_stop_token.hpp
                 ${PROJECT_SOURCE_DIR}/include/beman/execution/detail/has_as_awaitable.hpp
@@ -275,6 +276,7 @@ if(BEMAN_USE_MODULES)
                     get_domain_late.cppm
                     get_domain.cppm
                     get_env.cppm
+                    get_forward_progress_guarantee.cppm
                     get_scheduler.cppm
                     get_stop_token.cppm
                     has_as_awaitable.cppm

src/beman/execution/execution.cppm

@@ -31,6 +31,7 @@ export import beman.execution.detail.get_completion_signatures; // [exec.getcomp
 import beman.execution.detail.get_delegation_scheduler;
 import beman.execution.detail.get_domain;
 import beman.execution.detail.get_env;
+import beman.execution.detail.get_forward_progress_guarantee;
 import beman.execution.detail.get_scheduler;
 import beman.execution.detail.get_stop_token;
 export import beman.execution.detail.inplace_stop_source; // [stopsource.inplace], class inplace_stop_source
@@ -133,14 +134,14 @@ export using ::beman::execution::get_domain_t;
 export using ::beman::execution::get_scheduler_t;
 export using ::beman::execution::get_delegation_scheduler_t;
 export using ::beman::execution::get_await_completion_adaptor_t;
-//-dk:TODO export using ::beman::execution::get_forward_progress_guarantee_t;
+export using ::beman::execution::get_forward_progress_guarantee_t;
 
 export using ::beman::execution::get_domain;
 export using ::beman::execution::get_scheduler;
 export using ::beman::execution::get_delegation_scheduler;
 export using ::beman::execution::get_await_completion_adaptor;
-//-dk:TODO export using ::beman::execution::forward_progress_guarantee;
-//-dk:TODO export using ::beman::execution::get_forward_progress_guarantee;
+export using ::beman::execution::forward_progress_guarantee;
+export using ::beman::execution::get_forward_progress_guarantee;
 
 export using ::beman::execution::get_env_t;
 export using ::beman::execution::get_env;

src/beman/execution/get_forward_progress_guarantee.cppm

@@ -0,0 +1,13 @@
+module;
+// src/beman/execution/get_forward_progress_guarantee.cppm              -*-C++-*-
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+
+#include <beman/execution/detail/get_forward_progress_guarantee.hpp>
+
+export module beman.execution.detail.get_forward_progress_guarantee;
+
+namespace beman::execution {
+export using beman::execution::forward_progress_guarantee;
+export using beman::execution::get_forward_progress_guarantee_t;
+export using beman::execution::get_forward_progress_guarantee;
+} // namespace beman::execution

tests/beman/execution/exec-run-loop-general.test.cpp

@@ -28,4 +28,7 @@ TEST(exec_run_loop_general) {
     });
     static_assert(requires { rl.run(); });
     static_assert(requires { rl.finish(); });
+
+    ASSERT(test_std::get_forward_progress_guarantee(rl.get_scheduler()) ==
+           test_std::forward_progress_guarantee::parallel);
 }