diff options
| -rw-r--r-- | lib/events/event.h | 40 |
1 files changed, 20 insertions, 20 deletions
diff --git a/lib/events/event.h b/lib/events/event.h index 626a0229..309ebddf 100644 --- a/lib/events/event.h +++ b/lib/events/event.h @@ -298,7 +298,7 @@ using Events = EventsArray<Event>; // === is<>(), eventCast<>() and visit<>() === -template <typename EventT> +template <class EventT> inline bool is(const Event& e) { return e.type() == typeId<EventT>(); @@ -309,7 +309,7 @@ inline bool isUnknown(const Event& e) return e.type() == unknownEventTypeId(); } -template <typename EventT, typename BasePtrT> +template <class EventT, typename BasePtrT> inline auto eventCast(const BasePtrT& eptr) -> decltype(static_cast<EventT*>(&*eptr)) { @@ -319,7 +319,7 @@ inline auto eventCast(const BasePtrT& eptr) } // A single generic catch-all visitor -template <typename BaseEventT, typename FnT> +template <class BaseEventT, typename FnT> inline auto visit(const BaseEventT& event, FnT&& visitor) -> decltype(visitor(event)) { @@ -327,18 +327,17 @@ inline auto visit(const BaseEventT& event, FnT&& visitor) } namespace _impl { - template <typename T, typename FnT> - constexpr auto needs_downcast() - { - return !std::is_convertible_v<T, fn_arg_t<FnT>>; - } + template <class BaseT, typename FnT> + inline constexpr auto needs_downcast = + std::is_base_of_v<BaseT, std::decay_t<fn_arg_t<FnT>>> + && !std::is_same_v<BaseT, std::decay_t<fn_arg_t<FnT>>>; } // A single type-specific void visitor -template <typename BaseEventT, typename FnT> -inline std::enable_if_t<_impl::needs_downcast<BaseEventT, FnT>() +template <class BaseT, typename FnT> +inline auto visit(const BaseT& event, FnT&& visitor) + -> std::enable_if_t<_impl::needs_downcast<BaseT, FnT> && std::is_void_v<fn_return_t<FnT>>> -visit(const BaseEventT& event, FnT&& visitor) { using event_type = fn_arg_t<FnT>; if (is<std::decay_t<event_type>>(event)) @@ -347,10 +346,10 @@ visit(const BaseEventT& event, FnT&& visitor) // A single type-specific non-void visitor with an optional default value // non-voidness is guarded by defaultValue type -template <typename BaseEventT, typename FnT> -inline std::enable_if_t<_impl::needs_downcast<BaseEventT, FnT>(), fn_return_t<FnT>> -visit(const BaseEventT& event, FnT&& visitor, - fn_return_t<FnT>&& defaultValue = {}) +template <class BaseT, typename FnT> +inline auto visit(const BaseT& event, FnT&& visitor, + fn_return_t<FnT>&& defaultValue = {}) + -> std::enable_if_t<_impl::needs_downcast<BaseT, FnT>, fn_return_t<FnT>> { using event_type = fn_arg_t<FnT>; if (is<std::decay_t<event_type>>(event)) @@ -359,9 +358,10 @@ visit(const BaseEventT& event, FnT&& visitor, } // A chain of 2 or more visitors -template <typename BaseEventT, typename FnT1, typename FnT2, typename... FnTs> -inline fn_return_t<FnT1> visit(const BaseEventT& event, FnT1&& visitor1, - FnT2&& visitor2, FnTs&&... visitors) +template <class BaseT, typename FnT1, typename FnT2, typename... FnTs> +inline std::common_type_t<fn_return_t<FnT1>, fn_return_t<FnT2>> visit( + const BaseT& event, FnT1&& visitor1, FnT2&& visitor2, + FnTs&&... visitors) { using event_type1 = fn_arg_t<FnT1>; if (is<std::decay_t<event_type1>>(event)) @@ -374,8 +374,8 @@ inline fn_return_t<FnT1> visit(const BaseEventT& event, FnT1&& visitor1, // over a range of event pointers template <typename RangeT, typename... FnTs> inline auto visitEach(RangeT&& events, FnTs&&... visitors) - -> std::enable_if_t<std::is_convertible_v< - std::decay_t<decltype(**events.begin())>, Event>> + -> std::enable_if_t<std::is_void_v< + decltype(visit(**begin(events), std::forward<FnTs>(visitors)...))>> { for (auto&& evtPtr: events) visit(*evtPtr, std::forward<FnTs>(visitors)...); |