From 261e73bf3e01ec9b0caacea207c8cd6b47c78195 Mon Sep 17 00:00:00 2001
From: Michele Caini <michele.caini@gmail.com>
Date: Mon, 9 May 2022 12:07:13 +0200
Subject: [PATCH] y_combinator: conditionally noexcept

---
 src/entt/core/utility.hpp | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/src/entt/core/utility.hpp b/src/entt/core/utility.hpp
index c938f81d9..e38f68942 100644
--- a/src/entt/core/utility.hpp
+++ b/src/entt/core/utility.hpp
@@ -1,6 +1,7 @@
 #ifndef ENTT_CORE_UTILITY_HPP
 #define ENTT_CORE_UTILITY_HPP
 
+#include <type_traits>
 #include <utility>
 
 namespace entt {
@@ -71,7 +72,7 @@ struct y_combinator {
      * @brief Constructs a y-combinator from a given function.
      * @param recursive A potentially recursive function.
      */
-    constexpr y_combinator(Func recursive)
+    constexpr y_combinator(Func recursive) noexcept(std::is_nothrow_move_constructible_v<Func>)
         : func{std::move(recursive)} {}
 
     /**
@@ -81,13 +82,13 @@ struct y_combinator {
      * @return Return value of the underlying function, if any.
      */
     template<class... Args>
-    constexpr decltype(auto) operator()(Args &&...args) const {
+    constexpr decltype(auto) operator()(Args &&...args) const noexcept(std::is_nothrow_invocable_v<Func, const y_combinator &, Args...>) {
         return func(*this, std::forward<Args>(args)...);
     }
 
     /*! @copydoc operator()() */
     template<class... Args>
-    constexpr decltype(auto) operator()(Args &&...args) {
+    constexpr decltype(auto) operator()(Args &&...args) noexcept(std::is_nothrow_invocable_v<Func, y_combinator &, Args...>) {
         return func(*this, std::forward<Args>(args)...);
     }