entity: make entt_traits sfinae-friendly and avoid using std::underly…

…ing_type_t to define the entity traits types
lore14th · Jul 1, 2020 · 371b541 · 371b541
1 parent 902658f
commit 371b541
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Showing 5 changed files with 19 additions and 9 deletions.
diff --git a/src/entt/entity/entity.hpp b/src/entt/entity/entity.hpp
@@ -18,10 +18,20 @@ namespace entt {
  * Primary template isn't defined on purpose. All the specializations give a
  * compile-time error unless the template parameter is an accepted entity type.
  */
-template<typename>
+template<typename, typename = void>
 struct entt_traits;
 
 
+/**
+ * @brief Entity traits for enumeration types.
+ * @tparam Type The type to check.
+ */
+template<typename Type>
+struct entt_traits<Type, std::enable_if_t<std::is_enum_v<Type>>>
+ : entt_traits<std::underlying_type_t<Type>>
+{};
+
+
 /**
  * @brief Entity traits for a 16 bits entity identifier.
  *
@@ -111,7 +121,7 @@ namespace internal {
 
 class null {
  template<typename Entity>
- using traits_type = entt_traits<std::underlying_type_t<Entity>>;
+ using traits_type = entt_traits<Entity>;
 
 public:
  template<typename Entity>

diff --git a/src/entt/entity/registry.hpp b/src/entt/entity/registry.hpp
@@ -41,7 +41,7 @@ namespace entt {
  */
 template<typename Entity>
 class basic_registry {
- using traits_type = entt_traits<std::underlying_type_t<Entity>>;
+ using traits_type = entt_traits<Entity>;
 
  template<typename Component>
  struct pool_handler final: storage<Entity, Component> {

diff --git a/src/entt/entity/snapshot.hpp b/src/entt/entity/snapshot.hpp
@@ -32,7 +32,7 @@ class basic_snapshot {
  /*! @brief A registry is allowed to create snapshots. */
  friend class basic_registry<Entity>;
 
- using traits_type = entt_traits<std::underlying_type_t<Entity>>;
+ using traits_type = entt_traits<Entity>;
 
  template<typename Component, typename Archive, typename It>
  void get(Archive &archive, std::size_t sz, It first, It last) const {
@@ -164,7 +164,7 @@ class basic_snapshot_loader {
  /*! @brief A registry is allowed to create snapshot loaders. */
  friend class basic_registry<Entity>;
 
- using traits_type = entt_traits<std::underlying_type_t<Entity>>;
+ using traits_type = entt_traits<Entity>;
 
  template<typename Type, typename Archive>
  void assign(Archive &archive) const {
@@ -299,7 +299,7 @@ class basic_snapshot_loader {
  */
 template<typename Entity>
 class basic_continuous_loader {
- using traits_type = entt_traits<std::underlying_type_t<Entity>>;
+ using traits_type = entt_traits<Entity>;
 
  void destroy(Entity entt) {
  const auto it = remloc.find(entt);

diff --git a/src/entt/entity/sparse_set.hpp b/src/entt/entity/sparse_set.hpp
@@ -44,7 +44,7 @@ class sparse_set {
  static_assert(ENTT_PAGE_SIZE && ((ENTT_PAGE_SIZE & (ENTT_PAGE_SIZE - 1)) == 0), "ENTT_PAGE_SIZE must be a power of two");
  static constexpr auto entt_per_page = ENTT_PAGE_SIZE / sizeof(Entity);
 
- using traits_type = entt_traits<std::underlying_type_t<Entity>>;
+ using traits_type = entt_traits<Entity>;
  using page_type = std::unique_ptr<Entity[]>;
 
  class sparse_set_iterator final {

diff --git a/src/entt/entity/storage.hpp b/src/entt/entity/storage.hpp
@@ -49,7 +49,7 @@ class storage: public sparse_set<Entity> {
  static_assert(std::is_move_constructible_v<Type> && std::is_move_assignable_v<Type>, "The managed type must be at least move constructible and assignable");
 
  using underlying_type = sparse_set<Entity>;
- using traits_type = entt_traits<std::underlying_type_t<Entity>>;
+ using traits_type = entt_traits<Entity>;
 
  template<bool Const>
  class storage_iterator final {
@@ -478,7 +478,7 @@ class storage: public sparse_set<Entity> {
 /*! @copydoc storage */
 template<typename Entity, typename Type>
 class storage<Entity, Type, std::enable_if_t<ENTT_IS_EMPTY(Type)>>: public sparse_set<Entity> {
- using traits_type = entt_traits<std::underlying_type_t<Entity>>;
+ using traits_type = entt_traits<Entity>;
  using underlying_type = sparse_set<Entity>;
 
 public: