meta: export also the meta_node class template (close #464)

src/entt/meta/factory.hpp

@@ -392,11 +392,11 @@ public:
     auto alias(const id_type value) ENTT_NOEXCEPT {
         auto * const node = internal::meta_info<Type>::resolve();
 
-        ENTT_ASSERT(!exists(value, *internal::meta_info<>::global));
-        ENTT_ASSERT(!exists(node, *internal::meta_info<>::global));
+        ENTT_ASSERT(!exists(value, *internal::meta_context::global));
+        ENTT_ASSERT(!exists(node, *internal::meta_context::global));
         node->alias = value;
-        node->next = *internal::meta_info<>::global;
-        *internal::meta_info<>::global = node;
+        node->next = *internal::meta_context::global;
+        *internal::meta_context::global = node;
 
         return meta_factory<Type, Type>{&node->prop};
     }
@@ -779,7 +779,7 @@ public:
     auto reset() ENTT_NOEXCEPT {
         auto * const node = internal::meta_info<Type>::resolve();
 
-        internal::meta_info<>::detach(node);
+        internal::meta_context::detach(node);
 
         const auto unregister_all = y_combinator{
             [](auto &&self, auto **curr, auto... member) {
@@ -846,7 +846,7 @@ inline meta_type resolve() ENTT_NOEXCEPT {
 inline meta_type resolve(const id_type alias) ENTT_NOEXCEPT {
     return internal::find_if([alias](const auto *curr) {
         return curr->alias == alias;
-    }, *internal::meta_info<>::global);
+    }, *internal::meta_context::global);
 }
 
 
@@ -858,7 +858,7 @@ inline meta_type resolve(const id_type alias) ENTT_NOEXCEPT {
 template<typename Op>
 inline std::enable_if_t<std::is_invocable_v<Op, meta_type>, void>
 resolve(Op op) {
-    internal::visit<meta_type>(op, *internal::meta_info<>::global);
+    internal::visit<meta_type>(op, *internal::meta_context::global);
 }
 
 

src/entt/meta/meta.hpp

@@ -191,44 +191,11 @@ bool compare(const void *lhs, const void *rhs) {
 }
 
 
-template<typename... Type>
-struct meta_node {
-    static_assert(std::is_same_v<Type..., std::remove_cv_t<std::remove_reference_t<Type>>...>);
-
-    inline static meta_type_node * resolve() ENTT_NOEXCEPT {
-        static meta_type_node node{
-            type_info<Type...>::id(),
-            {},
-            nullptr,
-            nullptr,
-            std::is_void_v<Type...>,
-            std::is_integral_v<Type...>,
-            std::is_floating_point_v<Type...>,
-            std::is_array_v<Type...>,
-            std::is_enum_v<Type...>,
-            std::is_union_v<Type...>,
-            std::is_class_v<Type...>,
-            std::is_pointer_v<Type...>,
-            std::is_pointer_v<Type...> && std::is_function_v<std::remove_pointer_t<Type>...>,
-            std::is_member_object_pointer_v<Type...>,
-            std::is_member_function_pointer_v<Type...>,
-            std::extent_v<Type...>,
-            &compare<Type...>, // workaround for an issue with VS2017
-            &meta_node<std::remove_const_t<std::remove_pointer_t<Type>>...>::resolve,
-            &meta_node<std::remove_const_t<std::remove_extent_t<Type>>...>::resolve
-        };
-
-        return &node;
-    }
-};
-
-
-template<>
-struct meta_node<> {
+struct ENTT_API meta_context {
     inline static meta_type_node *local = nullptr;
     inline static meta_type_node **global = &local;
 
-    inline static void detach(const meta_type_node *node) ENTT_NOEXCEPT {
+    static void detach(const meta_type_node *node) ENTT_NOEXCEPT {
         auto **it = global;
 
         while(*it && *it != node) {
@@ -242,6 +209,38 @@ struct meta_node<> {
 };
 
 
+template<typename Type>
+struct ENTT_API meta_node {
+    static_assert(std::is_same_v<Type, std::remove_cv_t<std::remove_reference_t<Type>>>);
+
+    static meta_type_node * resolve() ENTT_NOEXCEPT {
+        static meta_type_node node{
+            type_info<Type>::id(),
+            {},
+            nullptr,
+            nullptr,
+            std::is_void_v<Type>,
+            std::is_integral_v<Type>,
+            std::is_floating_point_v<Type>,
+            std::is_array_v<Type>,
+            std::is_enum_v<Type>,
+            std::is_union_v<Type>,
+            std::is_class_v<Type>,
+            std::is_pointer_v<Type>,
+            std::is_pointer_v<Type> && std::is_function_v<std::remove_pointer_t<Type>>,
+            std::is_member_object_pointer_v<Type>,
+            std::is_member_function_pointer_v<Type>,
+            std::extent_v<Type>,
+            &compare<Type>, // workaround for an issue with VS2017
+            &meta_node<std::remove_const_t<std::remove_pointer_t<Type>>>::resolve,
+            &meta_node<std::remove_const_t<std::remove_extent_t<Type>>>::resolve
+        };
+
+        return &node;
+    }
+};
+
+
 template<typename... Type>
 struct meta_info: meta_node<std::remove_cv_t<std::remove_reference_t<Type>>...> {};
 
@@ -262,11 +261,11 @@ struct meta_ctx {
      * @param other A valid context to which to bind.
      */
     static void bind(meta_ctx other) ENTT_NOEXCEPT {
-        internal::meta_info<>::global = other.ctx;
+        internal::meta_context::global = other.ctx;
     }
 
 private:
-    internal::meta_type_node **ctx{&internal::meta_info<>::local};
+    internal::meta_type_node **ctx{&internal::meta_context::local};
 };
 
 
@@ -1487,7 +1486,7 @@ public:
 
     /*! @brief Removes a meta object from the list of searchable types. */
     void detach() ENTT_NOEXCEPT {
-        internal::meta_info<>::detach(node);
+        internal::meta_context::detach(node);
     }
 
 private:

test/entt/meta/meta.cpp

@@ -1875,7 +1875,7 @@ TEST_F(Meta, PropertiesAndCornerCases) {
 }
 
 TEST_F(Meta, Reset) {
-    ASSERT_NE(*entt::internal::meta_info<>::global, nullptr);
+    ASSERT_NE(*entt::internal::meta_context::global, nullptr);
 
     entt::meta<char>().reset();
     entt::meta<concrete_type>().reset();
@@ -1905,7 +1905,7 @@ TEST_F(Meta, Reset) {
     ASSERT_FALSE(entt::resolve("another_abstract_type"_hs));
     ASSERT_FALSE(entt::resolve("concrete"_hs));
 
-    ASSERT_EQ(*entt::internal::meta_info<>::global, nullptr);
+    ASSERT_EQ(*entt::internal::meta_context::global, nullptr);
 
     Meta::SetUpAfterUnregistration();
     entt::meta_any any{42.};

test/lib/meta/lib.cpp

@@ -8,9 +8,7 @@ position create_position(int x, int y) {
     return position{x, y};
 }
 
-ENTT_API void set_up(entt::meta_ctx ctx) {
-    entt::meta_ctx::bind(ctx);
-
+ENTT_API void set_up() {
     entt::meta<position>()
             .alias("position"_hs)
             .ctor<&create_position>()

test/lib/meta/main.cpp

@@ -4,19 +4,23 @@
 #include <entt/meta/meta.hpp>
 #include "types.h"
 
-ENTT_API void set_up(entt::meta_ctx);
+ENTT_API void set_up();
 ENTT_API void tear_down();
 ENTT_API entt::meta_any wrap_int(int);
 
 TEST(Lib, Meta) {
     ASSERT_FALSE(entt::resolve("position"_hs));
+    ASSERT_FALSE(entt::resolve("velocity"_hs));
 
-    set_up(entt::meta_ctx{});
+    set_up();
     entt::meta<double>().conv<int>();
 
     ASSERT_TRUE(entt::resolve("position"_hs));
     ASSERT_TRUE(entt::resolve("velocity"_hs));
 
+    ASSERT_EQ(entt::resolve<position>(), entt::resolve("position"_hs));
+    ASSERT_EQ(entt::resolve<velocity>(), entt::resolve("velocity"_hs));
+
     auto pos = entt::resolve("position"_hs).construct(42., 3.);
     auto vel = entt::resolve("velocity"_hs).ctor().invoke();