From 92fa032ff4ed8c9168f395409be84416c4e0c34b Mon Sep 17 00:00:00 2001
From: ThePhD <phdofthehouse@gmail.com>
Date: Sat, 4 Aug 2018 11:00:17 -0400
Subject: [PATCH] fix arity accumulation

---
 sol/types.hpp | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/sol/types.hpp b/sol/types.hpp
index 8357fa550..90efe329d 100644
--- a/sol/types.hpp
+++ b/sol/types.hpp
@@ -1046,6 +1046,12 @@ namespace sol {
 
 		template <typename C, C v, template <typename...> class V, typename T, typename... Args>
 		struct accumulate<C, v, V, T, Args...> : accumulate<C, v + V<T>::value, V, Args...> {};
+
+		template <typename C, C v, template <typename...> class V, typename List>
+		struct accumulate_list;
+
+		template <typename C, C v, template <typename...> class V, typename... Args>
+		struct accumulate_list<C, v, V, types<Args...>> : accumulate<C, v, V, Args...> {};
 	} // namespace detail
 
 	template <typename T>
@@ -1152,9 +1158,9 @@ namespace sol {
 	public:
 		typedef std::integral_constant<bool, meta::count_for<is_variadic_arguments, typename base_t::args_list>::value != 0> runtime_variadics_t;
 		static const std::size_t true_arity = base_t::arity;
-		static const std::size_t arity = base_t::arity - meta::count_for<is_transparent_argument, typename base_t::args_list>::value;
+		static const std::size_t arity = detail::accumulate_list<std::size_t, 0, lua_size, typename base_t::args_list>::value - meta::count_for<is_transparent_argument, typename base_t::args_list>::value;
 		static const std::size_t true_free_arity = base_t::free_arity;
-		static const std::size_t free_arity = base_t::free_arity - meta::count_for<is_transparent_argument, typename base_t::args_list>::value;
+		static const std::size_t free_arity = detail::accumulate_list<std::size_t, 0, lua_size, typename base_t::free_args_list>::value - meta::count_for<is_transparent_argument, typename base_t::args_list>::value;
 	};
 
 	template <typename T>