delegate: suppress warnings due to unused variables

src/entt/signal/delegate.hpp

@@ -68,7 +68,7 @@ class delegate<Ret(Args...)> {
     [[nodiscard]] auto wrap(std::index_sequence<Index...>) noexcept {
         return [](const void *, Args... args) -> Ret {
             [[maybe_unused]] const auto arguments = std::forward_as_tuple(std::forward<Args>(args)...);
-            constexpr auto offset = !std::is_invocable_r_v<Ret, decltype(Candidate), type_list_element_t<Index, type_list<Args...>>...> * (sizeof...(Args) - sizeof...(Index));
+            [[maybe_unused]] constexpr auto offset = !std::is_invocable_r_v<Ret, decltype(Candidate), type_list_element_t<Index, type_list<Args...>>...> * (sizeof...(Args) - sizeof...(Index));
             return static_cast<Ret>(std::invoke(Candidate, std::forward<type_list_element_t<Index + offset, type_list<Args...>>>(std::get<Index + offset>(arguments))...));
         };
     }
@@ -78,7 +78,7 @@ class delegate<Ret(Args...)> {
         return [](const void *payload, Args... args) -> Ret {
             Type *curr = static_cast<Type *>(const_cast<constness_as_t<void, Type> *>(payload));
             [[maybe_unused]] const auto arguments = std::forward_as_tuple(std::forward<Args>(args)...);
-            constexpr auto offset = !std::is_invocable_r_v<Ret, decltype(Candidate), Type &, type_list_element_t<Index, type_list<Args...>>...> * (sizeof...(Args) - sizeof...(Index));
+            [[maybe_unused]] constexpr auto offset = !std::is_invocable_r_v<Ret, decltype(Candidate), Type &, type_list_element_t<Index, type_list<Args...>>...> * (sizeof...(Args) - sizeof...(Index));
             return static_cast<Ret>(std::invoke(Candidate, *curr, std::forward<type_list_element_t<Index + offset, type_list<Args...>>>(std::get<Index + offset>(arguments))...));
         };
     }
@@ -88,7 +88,7 @@ class delegate<Ret(Args...)> {
         return [](const void *payload, Args... args) -> Ret {
             Type *curr = static_cast<Type *>(const_cast<constness_as_t<void, Type> *>(payload));
             [[maybe_unused]] const auto arguments = std::forward_as_tuple(std::forward<Args>(args)...);
-            constexpr auto offset = !std::is_invocable_r_v<Ret, decltype(Candidate), Type *, type_list_element_t<Index, type_list<Args...>>...> * (sizeof...(Args) - sizeof...(Index));
+            [[maybe_unused]] constexpr auto offset = !std::is_invocable_r_v<Ret, decltype(Candidate), Type *, type_list_element_t<Index, type_list<Args...>>...> * (sizeof...(Args) - sizeof...(Index));
             return static_cast<Ret>(std::invoke(Candidate, curr, std::forward<type_list_element_t<Index + offset, type_list<Args...>>>(std::get<Index + offset>(arguments))...));
         };
     }