Avoid unnecessary invoke_result uses in tag_fallback/override_invoke.hpp

pika-org · Mar 13, 2024 · b963fe0 · b963fe0
1 parent 797f072
commit b963fe0
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Showing 2 changed files with 10 additions and 6 deletions.
diff --git a/libs/pika/tag_invoke/include/pika/functional/detail/tag_fallback_invoke.hpp b/libs/pika/tag_invoke/include/pika/functional/detail/tag_fallback_invoke.hpp
@@ -103,6 +103,7 @@ namespace pika::functional::detail {
 
 # include <pika/config.hpp>
 # include <pika/functional/tag_invoke.hpp>
+# include <pika/type_support/type_identity.hpp>
 
 # include <type_traits>
 # include <utility>
@@ -196,11 +197,12 @@ namespace pika::functional::detail {
         is_nothrow_tag_fallback_invocable<Tag, Args...>::value;
 
     template <typename Tag, typename... Args>
-    using tag_fallback_invoke_result =
-        std::invoke_result<decltype(tag_fallback_invoke_ns::tag_fallback_invoke), Tag, Args...>;
+    using tag_fallback_invoke_result_t = decltype(tag_fallback_invoke_ns::tag_fallback_invoke(
+        std::declval<Tag>(), std::declval<Args>()...));
 
     template <typename Tag, typename... Args>
-    using tag_fallback_invoke_result_t = typename tag_fallback_invoke_result<Tag, Args...>::type;
+    using tag_fallback_invoke_result =
+        pika::detail::type_identity<tag_fallback_invoke_result_t<Tag, Args...>>;
 
     ///////////////////////////////////////////////////////////////////////////////
     namespace tag_base_ns {

diff --git a/libs/pika/tag_invoke/include/pika/functional/detail/tag_priority_invoke.hpp b/libs/pika/tag_invoke/include/pika/functional/detail/tag_priority_invoke.hpp
@@ -105,6 +105,7 @@ namespace pika::functional::detail {
 # include <pika/config.hpp>
 # include <pika/functional/detail/tag_fallback_invoke.hpp>
 # include <pika/functional/tag_invoke.hpp>
+# include <pika/type_support/type_identity.hpp>
 
 # include <type_traits>
 # include <utility>
@@ -199,11 +200,12 @@ namespace pika::functional::detail {
         is_nothrow_tag_override_invocable<Tag, Args...>::value;
 
     template <typename Tag, typename... Args>
-    using tag_override_invoke_result =
-        std::invoke_result<decltype(tag_override_invoke_ns::tag_override_invoke), Tag, Args...>;
+    using tag_override_invoke_result_t = decltype(tag_override_invoke_ns::tag_override_invoke(
+        std::declval<Tag>(), std::declval<Args>()...));
 
     template <typename Tag, typename... Args>
-    using tag_override_invoke_result_t = typename tag_override_invoke_result<Tag, Args...>::type;
+    using tag_override_invoke_result =
+        pika::detail::type_identity<tag_override_invoke_result_t<Tag, Args...>>;
 
     namespace tag_base_ns {
         // poison pill