refactored the virtual dtor into a base class

Author: dietmarkuehl

include/beman/execution26/detail/immovable.hpp

@@ -7,15 +7,27 @@
 // ----------------------------------------------------------------------------
 
 namespace beman::execution26::detail {
-struct immovable {
+struct immovable;
+struct virtual_immovable;
+} // namespace beman::execution26::detail
+
+struct beman::execution26::detail::immovable {
     constexpr immovable()                          = default;
     immovable(immovable&&)                         = delete;
     immovable(const immovable&)                    = delete;
     ~immovable()                                   = default;
     auto operator=(immovable&&) -> immovable&      = delete;
     auto operator=(const immovable&) -> immovable& = delete;
 };
-} // namespace beman::execution26::detail
+
+struct beman::execution26::detail::virtual_immovable {
+    constexpr virtual_immovable()                                  = default;
+    virtual_immovable(virtual_immovable&&)                         = delete;
+    virtual_immovable(const virtual_immovable&)                    = delete;
+    virtual ~virtual_immovable()                                   = default;
+    auto operator=(virtual_immovable&&) -> virtual_immovable&      = delete;
+    auto operator=(const virtual_immovable&) -> virtual_immovable& = delete;
+};
 
 // ----------------------------------------------------------------------------
 

include/beman/execution26/detail/inplace_stop_source.hpp

@@ -4,6 +4,7 @@
 #ifndef INCLUDED_BEMAN_EXECUTION26_DETAIL_INPLACE_STOP_SOURCE
 #define INCLUDED_BEMAN_EXECUTION26_DETAIL_INPLACE_STOP_SOURCE
 
+#include <beman/execution26/detail/immovable.hpp>
 #include <atomic>
 #include <memory>
 #include <mutex>
@@ -48,15 +49,8 @@ class beman::execution26::inplace_stop_token {
 // ----------------------------------------------------------------------------
 
 class beman::execution26::inplace_stop_source {
-    struct callback_base {
-        callback_base() = default;
-        callback_base(callback_base const&) = delete;
-        callback_base(callback_base&&) = delete;
-        virtual ~callback_base() = default;
-        auto operator=(callback_base const&) -> callback_base& = delete;
-        auto operator=(callback_base&&) -> callback_base& = delete;
-
-         callback_base* next{};
+    struct callback_base : public ::beman::execution26::detail::virtual_immovable {
+        callback_base* next{};
         virtual auto   call() -> void = 0;
     };
 

include/beman/execution26/detail/notify.hpp

@@ -28,13 +28,7 @@ class notifier : ::beman::execution26::detail::immovable {
 
   private:
     friend struct impls_for<::beman::execution26::detail::notify_t>;
-    struct base {
-        base() = default;
-        base(base const&) = default;
-        base(base&&) = default;
-        virtual ~base() = default;
-        auto operator=(base const&) -> base& = default;
-        auto operator=(base&&) -> base& = default;
+    struct base : ::beman::execution26::detail::virtual_immovable {
         base*        next{};
         virtual auto complete() -> void = 0;
     };

include/beman/execution26/detail/run_loop.hpp

@@ -37,16 +37,13 @@ class run_loop {
             return {this->loop};
         }
     };
-    struct opstate_base : ::beman::execution26::detail::immovable {
-        opstate_base() = default;
-        opstate_base(opstate_base const&) = delete;
-        opstate_base(opstate_base&&) = delete;
+
+    struct opstate_base : ::beman::execution26::detail::virtual_immovable {
         virtual ~opstate_base() = default;
-        auto operator=(opstate_base const&) -> opstate_base& = delete;
-        auto operator=(opstate_base&&) -> opstate_base& = delete;
         opstate_base* next{};
         virtual auto  execute() noexcept -> void = 0;
     };
+
     template <typename Receiver>
     struct opstate : opstate_base {
         using operation_state_concept = ::beman::execution26::operation_state_t;