feat: make IoAwaitables composable as std::execution senders

example/awaitable-sender/CMakeLists.txt

@@ -17,20 +17,27 @@ FetchContent_Declare(
 )
 FetchContent_MakeAvailable(execution)
 
-file(GLOB_RECURSE PFILES CONFIGURE_DEPENDS *.cpp *.hpp
-    CMakeLists.txt
-    Jamfile)
-
-source_group(TREE ${CMAKE_CURRENT_SOURCE_DIR} PREFIX "" FILES ${PFILES})
-
-add_executable(capy_example_awaitable_sender ${PFILES})
-
-set_property(TARGET capy_example_awaitable_sender
-    PROPERTY FOLDER "examples")
-
-target_compile_features(capy_example_awaitable_sender
-    PRIVATE cxx_std_23)
-
-target_link_libraries(capy_example_awaitable_sender
-    Boost::capy
-    beman::execution_headers)
+add_executable(capy_example_awaitable_sender
+    awaitable_sender.cpp
+    awaitable_sender.hpp
+    awaitable_sender_base.hpp
+    awaitable_sender_detail.hpp
+    read_op.hpp)
+
+add_executable(capy_example_awaitable_sender_test
+    tests.cpp
+    awaitable_sender.hpp
+    awaitable_sender_base.hpp
+    awaitable_sender_detail.hpp
+    read_op.hpp)
+
+foreach(tgt capy_example_awaitable_sender capy_example_awaitable_sender_test)
+    set_property(TARGET ${tgt} PROPERTY FOLDER "examples")
+    target_compile_features(${tgt} PRIVATE cxx_std_23)
+    target_link_libraries(${tgt}
+        Boost::capy
+        beman::execution_headers)
+endforeach()
+
+add_test(NAME capy_example_awaitable_sender_test
+    COMMAND capy_example_awaitable_sender_test)

example/awaitable-sender/awaitable_sender.cpp

@@ -9,6 +9,8 @@
 //
 
 #include "awaitable_sender.hpp"
+#include "awaitable_sender_base.hpp"
+#include "read_op.hpp"
 
 #include <boost/capy.hpp>
 
@@ -180,6 +182,28 @@ int main()
     done4.wait();
     std::cout << "  split_ec error test done\n";
 
+    // A native awaitable-sender: read_op derives
+    // awaitable_sender_base, no as_sender() wrapping.
+    std::cout << "\n--- native awaitable-sender test ---\n";
+    std::latch done5(1);
+
+    auto rop = capy::read_op::result({}, 42);
+    auto op5 = ex::connect(
+        ex::then(
+            std::move(rop),
+            [](std::size_t n)
+            {
+                std::cout
+                    << "  read " << n << " bytes\n";
+            }),
+        demo_receiver{
+            {pool_ex, std::stop_token{}},
+            &done5});
+
+    ex::start(op5);
+    done5.wait();
+    std::cout << "  native awaitable-sender test done\n";
+
     // All demos have drained; safe to join the waker thread now.
     waker_thread.join();
 }