/// std::is_nothrow_invocable
template<typename _Fn, typename... _ArgTypes>
struct is_nothrow_invocable
+#if _GLIBCXX_USE_BUILTIN_TRAIT(__is_nothrow_invocable)
+ : public __bool_constant<__is_nothrow_invocable(_Fn, _ArgTypes...)>
+#else
: __and_<__is_invocable_impl<__invoke_result<_Fn, _ArgTypes...>, void>,
__call_is_nothrow_<_Fn, _ArgTypes...>>::type
+#endif
{
static_assert(std::__is_complete_or_unbounded(__type_identity<_Fn>{}),
"_Fn must be a complete class or an unbounded array");