update single include file

CMakeLists.txt

@@ -282,7 +282,13 @@ install(
     DESTINATION ${CMAKE_INSTALL_LIBDIR}/EnTT/cmake
 )
 
-install(DIRECTORY src/ DESTINATION ${CMAKE_INSTALL_INCLUDEDIR})
+install(
+    DIRECTORY src/
+    DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}
+    FILES_MATCHING
+    PATTERN "*.h"
+    PATTERN "*.hpp"
+)
 
 export(PACKAGE EnTT)
 

single_include/entt/entt.hpp

@@ -19,7 +19,7 @@
 
 #define ENTT_VERSION_MAJOR 3
 #define ENTT_VERSION_MINOR 13
-#define ENTT_VERSION_PATCH 0
+#define ENTT_VERSION_PATCH 1
 
 #define ENTT_VERSION \
     ENTT_XSTR(ENTT_VERSION_MAJOR) \
@@ -127,7 +127,7 @@
 
 #define ENTT_VERSION_MAJOR 3
 #define ENTT_VERSION_MINOR 13
-#define ENTT_VERSION_PATCH 0
+#define ENTT_VERSION_PATCH 1
 
 #define ENTT_VERSION \
     ENTT_XSTR(ENTT_VERSION_MAJOR) \
@@ -169,7 +169,7 @@
 
 #define ENTT_VERSION_MAJOR 3
 #define ENTT_VERSION_MINOR 13
-#define ENTT_VERSION_PATCH 0
+#define ENTT_VERSION_PATCH 1
 
 #define ENTT_VERSION \
     ENTT_XSTR(ENTT_VERSION_MAJOR) \
@@ -296,7 +296,7 @@
 
 #define ENTT_VERSION_MAJOR 3
 #define ENTT_VERSION_MINOR 13
-#define ENTT_VERSION_PATCH 0
+#define ENTT_VERSION_PATCH 1
 
 #define ENTT_VERSION \
     ENTT_XSTR(ENTT_VERSION_MAJOR) \
@@ -5248,7 +5248,7 @@ struct radix_sort {
 
 #define ENTT_VERSION_MAJOR 3
 #define ENTT_VERSION_MINOR 13
-#define ENTT_VERSION_PATCH 0
+#define ENTT_VERSION_PATCH 1
 
 #define ENTT_VERSION \
     ENTT_XSTR(ENTT_VERSION_MAJOR) \
@@ -10297,7 +10297,7 @@ private:
 
 #define ENTT_VERSION_MAJOR 3
 #define ENTT_VERSION_MINOR 13
-#define ENTT_VERSION_PATCH 0
+#define ENTT_VERSION_PATCH 1
 
 #define ENTT_VERSION \
     ENTT_XSTR(ENTT_VERSION_MAJOR) \
@@ -10419,7 +10419,7 @@ private:
 
 #define ENTT_VERSION_MAJOR 3
 #define ENTT_VERSION_MINOR 13
-#define ENTT_VERSION_PATCH 0
+#define ENTT_VERSION_PATCH 1
 
 #define ENTT_VERSION \
     ENTT_XSTR(ENTT_VERSION_MAJOR) \
@@ -18188,27 +18188,28 @@ class group_handler<owned_t<Owned...>, get_t<Get...>, exclude_t<Exclude...>> fin
     using base_type = std::common_type_t<typename Owned::base_type..., typename Get::base_type..., typename Exclude::base_type...>;
     using entity_type = typename base_type::entity_type;
 
-    void swap_elements(const std::size_t pos, const entity_type entt) {
-        std::apply([pos, entt](auto *...cpool) { (cpool->swap_elements(cpool->data()[pos], entt), ...); }, pools);
+    template<std::size_t... Index>
+    void swap_elements(const std::size_t pos, const entity_type entt, std::index_sequence<Index...>) {
+        (std::get<Index>(pools)->swap_elements(std::get<Index>(pools)->data()[pos], entt), ...);
     }
 
     void push_on_construct(const entity_type entt) {
         if(std::apply([entt, len = len](auto *cpool, auto *...other) { return cpool->contains(entt) && !(cpool->index(entt) < len) && (other->contains(entt) && ...); }, pools)
            && std::apply([entt](auto *...cpool) { return (!cpool->contains(entt) && ...); }, filter)) {
-            swap_elements(len++, entt);
+            swap_elements(len++, entt, std::index_sequence_for<Owned...>{});
         }
     }
 
     void push_on_destroy(const entity_type entt) {
         if(std::apply([entt, len = len](auto *cpool, auto *...other) { return cpool->contains(entt) && !(cpool->index(entt) < len) && (other->contains(entt) && ...); }, pools)
            && std::apply([entt](auto *...cpool) { return (0u + ... + cpool->contains(entt)) == 1u; }, filter)) {
-            swap_elements(len++, entt);
+            swap_elements(len++, entt, std::index_sequence_for<Owned...>{});
         }
     }
 
     void remove_if(const entity_type entt) {
         if(std::get<0>(pools)->contains(entt) && (std::get<0>(pools)->index(entt) < len)) {
-            swap_elements(--len, entt);
+            swap_elements(--len, entt, std::index_sequence_for<Owned...>{});
         }
     }
 
@@ -18242,13 +18243,11 @@ public:
         return len;
     }
 
-    template<typename Type>
-    Type pools_as() const noexcept {
+    auto pools_as_tuple() const noexcept {
         return pools;
     }
 
-    template<typename Type>
-    Type filter_as() const noexcept {
+    auto filter_as_tuple() const noexcept {
         return filter;
     }
 
@@ -18310,13 +18309,11 @@ public:
         return elem;
     }
 
-    template<typename Type>
-    Type pools_as() const noexcept {
+    auto pools_as_tuple() const noexcept {
         return pools;
     }
 
-    template<typename Type>
-    Type filter_as() const noexcept {
+    auto filter_as_tuple() const noexcept {
         return filter;
     }
 
@@ -18370,12 +18367,12 @@ class basic_group<owned_t<>, get_t<Get...>, exclude_t<Exclude...>> {
 
     auto pools() const noexcept {
         using return_type = std::tuple<Get *...>;
-        return descriptor ? descriptor->template pools_as<return_type>() : return_type{};
+        return descriptor ? descriptor->pools_as_tuple() : return_type{};
     }
 
     auto filter() const noexcept {
         using return_type = std::tuple<Exclude *...>;
-        return descriptor ? descriptor->template filter_as<return_type>() : return_type{};
+        return descriptor ? descriptor->filter_as_tuple() : return_type{};
     }
 
 public:
@@ -18791,12 +18788,12 @@ class basic_group<owned_t<Owned...>, get_t<Get...>, exclude_t<Exclude...>> {
 
     auto pools() const noexcept {
         using return_type = std::tuple<Owned *..., Get *...>;
-        return descriptor ? descriptor->template pools_as<return_type>() : return_type{};
+        return descriptor ? descriptor->pools_as_tuple() : return_type{};
     }
 
     auto filter() const noexcept {
         using return_type = std::tuple<Exclude *...>;
-        return descriptor ? descriptor->template filter_as<return_type>() : return_type{};
+        return descriptor ? descriptor->filter_as_tuple() : return_type{};
     }
 
 public:
@@ -19569,7 +19566,7 @@ template<typename... Args, typename... Other>
 
 #define ENTT_VERSION_MAJOR 3
 #define ENTT_VERSION_MINOR 13
-#define ENTT_VERSION_PATCH 0
+#define ENTT_VERSION_PATCH 1
 
 #define ENTT_VERSION \
     ENTT_XSTR(ENTT_VERSION_MAJOR) \
@@ -19688,7 +19685,7 @@ template<typename... Args, typename... Other>
 
 #define ENTT_VERSION_MAJOR 3
 #define ENTT_VERSION_MINOR 13
-#define ENTT_VERSION_PATCH 0
+#define ENTT_VERSION_PATCH 1
 
 #define ENTT_VERSION \
     ENTT_XSTR(ENTT_VERSION_MAJOR) \
@@ -21214,27 +21211,28 @@ class group_handler<owned_t<Owned...>, get_t<Get...>, exclude_t<Exclude...>> fin
     using base_type = std::common_type_t<typename Owned::base_type..., typename Get::base_type..., typename Exclude::base_type...>;
     using entity_type = typename base_type::entity_type;
 
-    void swap_elements(const std::size_t pos, const entity_type entt) {
-        std::apply([pos, entt](auto *...cpool) { (cpool->swap_elements(cpool->data()[pos], entt), ...); }, pools);
+    template<std::size_t... Index>
+    void swap_elements(const std::size_t pos, const entity_type entt, std::index_sequence<Index...>) {
+        (std::get<Index>(pools)->swap_elements(std::get<Index>(pools)->data()[pos], entt), ...);
     }
 
     void push_on_construct(const entity_type entt) {
         if(std::apply([entt, len = len](auto *cpool, auto *...other) { return cpool->contains(entt) && !(cpool->index(entt) < len) && (other->contains(entt) && ...); }, pools)
            && std::apply([entt](auto *...cpool) { return (!cpool->contains(entt) && ...); }, filter)) {
-            swap_elements(len++, entt);
+            swap_elements(len++, entt, std::index_sequence_for<Owned...>{});
         }
     }
 
     void push_on_destroy(const entity_type entt) {
         if(std::apply([entt, len = len](auto *cpool, auto *...other) { return cpool->contains(entt) && !(cpool->index(entt) < len) && (other->contains(entt) && ...); }, pools)
            && std::apply([entt](auto *...cpool) { return (0u + ... + cpool->contains(entt)) == 1u; }, filter)) {
-            swap_elements(len++, entt);
+            swap_elements(len++, entt, std::index_sequence_for<Owned...>{});
         }
     }
 
     void remove_if(const entity_type entt) {
         if(std::get<0>(pools)->contains(entt) && (std::get<0>(pools)->index(entt) < len)) {
-            swap_elements(--len, entt);
+            swap_elements(--len, entt, std::index_sequence_for<Owned...>{});
         }
     }
 
@@ -21268,13 +21266,11 @@ public:
         return len;
     }
 
-    template<typename Type>
-    Type pools_as() const noexcept {
+    auto pools_as_tuple() const noexcept {
         return pools;
     }
 
-    template<typename Type>
-    Type filter_as() const noexcept {
+    auto filter_as_tuple() const noexcept {
         return filter;
     }
 
@@ -21336,13 +21332,11 @@ public:
         return elem;
     }
 
-    template<typename Type>
-    Type pools_as() const noexcept {
+    auto pools_as_tuple() const noexcept {
         return pools;
     }
 
-    template<typename Type>
-    Type filter_as() const noexcept {
+    auto filter_as_tuple() const noexcept {
         return filter;
     }
 
@@ -21396,12 +21390,12 @@ class basic_group<owned_t<>, get_t<Get...>, exclude_t<Exclude...>> {
 
     auto pools() const noexcept {
         using return_type = std::tuple<Get *...>;
-        return descriptor ? descriptor->template pools_as<return_type>() : return_type{};
+        return descriptor ? descriptor->pools_as_tuple() : return_type{};
     }
 
     auto filter() const noexcept {
         using return_type = std::tuple<Exclude *...>;
-        return descriptor ? descriptor->template filter_as<return_type>() : return_type{};
+        return descriptor ? descriptor->filter_as_tuple() : return_type{};
     }
 
 public:
@@ -21817,12 +21811,12 @@ class basic_group<owned_t<Owned...>, get_t<Get...>, exclude_t<Exclude...>> {
 
     auto pools() const noexcept {
         using return_type = std::tuple<Owned *..., Get *...>;
-        return descriptor ? descriptor->template pools_as<return_type>() : return_type{};
+        return descriptor ? descriptor->pools_as_tuple() : return_type{};
     }
 
     auto filter() const noexcept {
         using return_type = std::tuple<Exclude *...>;
-        return descriptor ? descriptor->template filter_as<return_type>() : return_type{};
+        return descriptor ? descriptor->filter_as_tuple() : return_type{};
     }
 
 public:
@@ -25126,7 +25120,7 @@ private:
 
 #define ENTT_VERSION_MAJOR 3
 #define ENTT_VERSION_MINOR 13
-#define ENTT_VERSION_PATCH 0
+#define ENTT_VERSION_PATCH 1
 
 #define ENTT_VERSION \
     ENTT_XSTR(ENTT_VERSION_MAJOR) \
@@ -25446,7 +25440,7 @@ private:
 
 #define ENTT_VERSION_MAJOR 3
 #define ENTT_VERSION_MINOR 13
-#define ENTT_VERSION_PATCH 0
+#define ENTT_VERSION_PATCH 1
 
 #define ENTT_VERSION \
     ENTT_XSTR(ENTT_VERSION_MAJOR) \
@@ -25952,7 +25946,7 @@ private:
 
 #define ENTT_VERSION_MAJOR 3
 #define ENTT_VERSION_MINOR 13
-#define ENTT_VERSION_PATCH 0
+#define ENTT_VERSION_PATCH 1
 
 #define ENTT_VERSION \
     ENTT_XSTR(ENTT_VERSION_MAJOR) \
@@ -26079,7 +26073,7 @@ private:
 
 #define ENTT_VERSION_MAJOR 3
 #define ENTT_VERSION_MINOR 13
-#define ENTT_VERSION_PATCH 0
+#define ENTT_VERSION_PATCH 1
 
 #define ENTT_VERSION \
     ENTT_XSTR(ENTT_VERSION_MAJOR) \
@@ -33480,7 +33474,7 @@ private:
 
 #define ENTT_VERSION_MAJOR 3
 #define ENTT_VERSION_MINOR 13
-#define ENTT_VERSION_PATCH 0
+#define ENTT_VERSION_PATCH 1
 
 #define ENTT_VERSION \
     ENTT_XSTR(ENTT_VERSION_MAJOR) \
@@ -33607,7 +33601,7 @@ private:
 
 #define ENTT_VERSION_MAJOR 3
 #define ENTT_VERSION_MINOR 13
-#define ENTT_VERSION_PATCH 0
+#define ENTT_VERSION_PATCH 1
 
 #define ENTT_VERSION \
     ENTT_XSTR(ENTT_VERSION_MAJOR) \
@@ -39350,7 +39344,7 @@ public:
     basic_snapshot_loader(registry_type &source) noexcept
         : reg{&source} {
         // restoring a snapshot as a whole requires a clean registry
-        ENTT_ASSERT(reg->template storage<entity_type>().empty() && (reg->storage().begin() == reg->storage().end()), "Registry must be empty");
+        ENTT_ASSERT(reg->template storage<entity_type>().free_list() == 0u, "Registry must be empty");
     }
 
     /*! @brief Default move constructor. */
@@ -42964,7 +42958,7 @@ basic_view(std::tuple<Get &...>, std::tuple<Exclude &...> = {}) -> basic_view<ge
 
 #define ENTT_VERSION_MAJOR 3
 #define ENTT_VERSION_MINOR 13
-#define ENTT_VERSION_PATCH 0
+#define ENTT_VERSION_PATCH 1
 
 #define ENTT_VERSION \
     ENTT_XSTR(ENTT_VERSION_MAJOR) \
@@ -43284,7 +43278,7 @@ private:
 
 #define ENTT_VERSION_MAJOR 3
 #define ENTT_VERSION_MINOR 13
-#define ENTT_VERSION_PATCH 0
+#define ENTT_VERSION_PATCH 1
 
 #define ENTT_VERSION \
     ENTT_XSTR(ENTT_VERSION_MAJOR) \
@@ -43851,7 +43845,7 @@ void dot(std::ostream &out, const Graph &graph) {
 
 #define ENTT_VERSION_MAJOR 3
 #define ENTT_VERSION_MINOR 13
-#define ENTT_VERSION_PATCH 0
+#define ENTT_VERSION_PATCH 1
 
 #define ENTT_VERSION \
     ENTT_XSTR(ENTT_VERSION_MAJOR) \
@@ -43978,7 +43972,7 @@ void dot(std::ostream &out, const Graph &graph) {
 
 #define ENTT_VERSION_MAJOR 3
 #define ENTT_VERSION_MINOR 13
-#define ENTT_VERSION_PATCH 0
+#define ENTT_VERSION_PATCH 1
 
 #define ENTT_VERSION \
     ENTT_XSTR(ENTT_VERSION_MAJOR) \
@@ -50681,7 +50675,7 @@ private:
 
 #define ENTT_VERSION_MAJOR 3
 #define ENTT_VERSION_MINOR 13
-#define ENTT_VERSION_PATCH 0
+#define ENTT_VERSION_PATCH 1
 
 #define ENTT_VERSION \
     ENTT_XSTR(ENTT_VERSION_MAJOR) \
@@ -50998,7 +50992,7 @@ struct adl_meta_pointer_like {
 
 #define ENTT_VERSION_MAJOR 3
 #define ENTT_VERSION_MINOR 13
-#define ENTT_VERSION_PATCH 0
+#define ENTT_VERSION_PATCH 1
 
 #define ENTT_VERSION \
     ENTT_XSTR(ENTT_VERSION_MAJOR) \
@@ -51125,7 +51119,7 @@ struct adl_meta_pointer_like {
 
 #define ENTT_VERSION_MAJOR 3
 #define ENTT_VERSION_MINOR 13
-#define ENTT_VERSION_PATCH 0
+#define ENTT_VERSION_PATCH 1
 
 #define ENTT_VERSION \
     ENTT_XSTR(ENTT_VERSION_MAJOR) \
@@ -55838,7 +55832,7 @@ private:
 
 #define ENTT_VERSION_MAJOR 3
 #define ENTT_VERSION_MINOR 13
-#define ENTT_VERSION_PATCH 0
+#define ENTT_VERSION_PATCH 1
 
 #define ENTT_VERSION \
     ENTT_XSTR(ENTT_VERSION_MAJOR) \
@@ -56122,7 +56116,7 @@ class meta_ctx: private internal::meta_context {
 
 #define ENTT_VERSION_MAJOR 3
 #define ENTT_VERSION_MINOR 13
-#define ENTT_VERSION_PATCH 0
+#define ENTT_VERSION_PATCH 1
 
 #define ENTT_VERSION \
     ENTT_XSTR(ENTT_VERSION_MAJOR) \
@@ -59830,7 +59824,7 @@ struct std::tuple_element<Index, entt::value_list<Value...>>: entt::value_list_e
 
 #define ENTT_VERSION_MAJOR 3
 #define ENTT_VERSION_MINOR 13
-#define ENTT_VERSION_PATCH 0
+#define ENTT_VERSION_PATCH 1
 
 #define ENTT_VERSION \
     ENTT_XSTR(ENTT_VERSION_MAJOR) \
@@ -67805,7 +67799,7 @@ using invoke_result_t = typename std::invoke_result<Func, Args...>::type;
 
 #define ENTT_VERSION_MAJOR 3
 #define ENTT_VERSION_MINOR 13
-#define ENTT_VERSION_PATCH 0
+#define ENTT_VERSION_PATCH 1
 
 #define ENTT_VERSION \
     ENTT_XSTR(ENTT_VERSION_MAJOR) \
@@ -71981,7 +71975,7 @@ struct process_adaptor: process<process_adaptor<Func, Delta>, Delta>, private Fu
 
 #define ENTT_VERSION_MAJOR 3
 #define ENTT_VERSION_MINOR 13
-#define ENTT_VERSION_PATCH 0
+#define ENTT_VERSION_PATCH 1
 
 #define ENTT_VERSION \
     ENTT_XSTR(ENTT_VERSION_MAJOR) \
@@ -72108,7 +72102,7 @@ struct process_adaptor: process<process_adaptor<Func, Delta>, Delta>, private Fu
 
 #define ENTT_VERSION_MAJOR 3
 #define ENTT_VERSION_MINOR 13
-#define ENTT_VERSION_PATCH 0
+#define ENTT_VERSION_PATCH 1
 
 #define ENTT_VERSION \
     ENTT_XSTR(ENTT_VERSION_MAJOR) \
@@ -74120,7 +74114,7 @@ private:
 
 #define ENTT_VERSION_MAJOR 3
 #define ENTT_VERSION_MINOR 13
-#define ENTT_VERSION_PATCH 0
+#define ENTT_VERSION_PATCH 1
 
 #define ENTT_VERSION \
     ENTT_XSTR(ENTT_VERSION_MAJOR) \
@@ -74247,7 +74241,7 @@ private:
 
 #define ENTT_VERSION_MAJOR 3
 #define ENTT_VERSION_MINOR 13
-#define ENTT_VERSION_PATCH 0
+#define ENTT_VERSION_PATCH 1
 
 #define ENTT_VERSION \
     ENTT_XSTR(ENTT_VERSION_MAJOR) \
@@ -78034,7 +78028,7 @@ struct uses_allocator<entt::internal::dense_map_node<Key, Value>, Allocator>
 
 #define ENTT_VERSION_MAJOR 3
 #define ENTT_VERSION_MINOR 13
-#define ENTT_VERSION_PATCH 0
+#define ENTT_VERSION_PATCH 1
 
 #define ENTT_VERSION \
     ENTT_XSTR(ENTT_VERSION_MAJOR) \
@@ -80659,7 +80653,7 @@ template<typename Lhs, typename Rhs>
 
 #define ENTT_VERSION_MAJOR 3
 #define ENTT_VERSION_MINOR 13
-#define ENTT_VERSION_PATCH 0
+#define ENTT_VERSION_PATCH 1
 
 #define ENTT_VERSION \
     ENTT_XSTR(ENTT_VERSION_MAJOR) \
@@ -80778,7 +80772,7 @@ template<typename Lhs, typename Rhs>
 
 #define ENTT_VERSION_MAJOR 3
 #define ENTT_VERSION_MINOR 13
-#define ENTT_VERSION_PATCH 0
+#define ENTT_VERSION_PATCH 1
 
 #define ENTT_VERSION \
     ENTT_XSTR(ENTT_VERSION_MAJOR) \
@@ -82225,7 +82219,7 @@ delegate(Ret (*)(const void *, Args...), const void * = nullptr) -> delegate<Ret
 
 #define ENTT_VERSION_MAJOR 3
 #define ENTT_VERSION_MINOR 13
-#define ENTT_VERSION_PATCH 0
+#define ENTT_VERSION_PATCH 1
 
 #define ENTT_VERSION \
     ENTT_XSTR(ENTT_VERSION_MAJOR) \
@@ -82352,7 +82346,7 @@ delegate(Ret (*)(const void *, Args...), const void * = nullptr) -> delegate<Ret
 
 #define ENTT_VERSION_MAJOR 3
 #define ENTT_VERSION_MINOR 13
-#define ENTT_VERSION_PATCH 0
+#define ENTT_VERSION_PATCH 1
 
 #define ENTT_VERSION \
     ENTT_XSTR(ENTT_VERSION_MAJOR) \

src/entt/config/version.h

@@ -5,7 +5,7 @@
 
 #define ENTT_VERSION_MAJOR 3
 #define ENTT_VERSION_MINOR 13
-#define ENTT_VERSION_PATCH 0
+#define ENTT_VERSION_PATCH 1
 
 #define ENTT_VERSION \
     ENTT_XSTR(ENTT_VERSION_MAJOR) \

src/entt/entity/group.hpp

@@ -109,27 +109,28 @@ class group_handler<owned_t<Owned...>, get_t<Get...>, exclude_t<Exclude...>> fin
     using base_type = std::common_type_t<typename Owned::base_type..., typename Get::base_type..., typename Exclude::base_type...>;
     using entity_type = typename base_type::entity_type;
 
-    void swap_elements(const std::size_t pos, const entity_type entt) {
-        std::apply([pos, entt](auto *...cpool) { (cpool->swap_elements(cpool->data()[pos], entt), ...); }, pools);
+    template<std::size_t... Index>
+    void swap_elements(const std::size_t pos, const entity_type entt, std::index_sequence<Index...>) {
+        (std::get<Index>(pools)->swap_elements(std::get<Index>(pools)->data()[pos], entt), ...);
     }
 
     void push_on_construct(const entity_type entt) {
         if(std::apply([entt, len = len](auto *cpool, auto *...other) { return cpool->contains(entt) && !(cpool->index(entt) < len) && (other->contains(entt) && ...); }, pools)
            && std::apply([entt](auto *...cpool) { return (!cpool->contains(entt) && ...); }, filter)) {
-            swap_elements(len++, entt);
+            swap_elements(len++, entt, std::index_sequence_for<Owned...>{});
         }
     }
 
     void push_on_destroy(const entity_type entt) {
         if(std::apply([entt, len = len](auto *cpool, auto *...other) { return cpool->contains(entt) && !(cpool->index(entt) < len) && (other->contains(entt) && ...); }, pools)
            && std::apply([entt](auto *...cpool) { return (0u + ... + cpool->contains(entt)) == 1u; }, filter)) {
-            swap_elements(len++, entt);
+            swap_elements(len++, entt, std::index_sequence_for<Owned...>{});
         }
     }
 
     void remove_if(const entity_type entt) {
         if(std::get<0>(pools)->contains(entt) && (std::get<0>(pools)->index(entt) < len)) {
-            swap_elements(--len, entt);
+            swap_elements(--len, entt, std::index_sequence_for<Owned...>{});
         }
     }
 
@@ -163,13 +164,11 @@ public:
         return len;
     }
 
-    template<typename Type>
-    Type pools_as() const noexcept {
+    auto pools_as_tuple() const noexcept {
         return pools;
     }
 
-    template<typename Type>
-    Type filter_as() const noexcept {
+    auto filter_as_tuple() const noexcept {
         return filter;
     }
 
@@ -231,13 +230,11 @@ public:
         return elem;
     }
 
-    template<typename Type>
-    Type pools_as() const noexcept {
+    auto pools_as_tuple() const noexcept {
         return pools;
     }
 
-    template<typename Type>
-    Type filter_as() const noexcept {
+    auto filter_as_tuple() const noexcept {
         return filter;
     }
 
@@ -291,12 +288,12 @@ class basic_group<owned_t<>, get_t<Get...>, exclude_t<Exclude...>> {
 
     auto pools() const noexcept {
         using return_type = std::tuple<Get *...>;
-        return descriptor ? descriptor->template pools_as<return_type>() : return_type{};
+        return descriptor ? descriptor->pools_as_tuple() : return_type{};
     }
 
     auto filter() const noexcept {
         using return_type = std::tuple<Exclude *...>;
-        return descriptor ? descriptor->template filter_as<return_type>() : return_type{};
+        return descriptor ? descriptor->filter_as_tuple() : return_type{};
     }
 
 public:
@@ -712,12 +709,12 @@ class basic_group<owned_t<Owned...>, get_t<Get...>, exclude_t<Exclude...>> {
 
     auto pools() const noexcept {
         using return_type = std::tuple<Owned *..., Get *...>;
-        return descriptor ? descriptor->template pools_as<return_type>() : return_type{};
+        return descriptor ? descriptor->pools_as_tuple() : return_type{};
     }
 
     auto filter() const noexcept {
         using return_type = std::tuple<Exclude *...>;
-        return descriptor ? descriptor->template filter_as<return_type>() : return_type{};
+        return descriptor ? descriptor->filter_as_tuple() : return_type{};
     }
 
 public:

src/entt/entity/snapshot.hpp

@@ -164,7 +164,7 @@ public:
     basic_snapshot_loader(registry_type &source) noexcept
         : reg{&source} {
         // restoring a snapshot as a whole requires a clean registry
-        ENTT_ASSERT(reg->template storage<entity_type>().empty() && (reg->storage().begin() == reg->storage().end()), "Registry must be empty");
+        ENTT_ASSERT(reg->template storage<entity_type>().free_list() == 0u, "Registry must be empty");
     }
 
     /*! @brief Default move constructor. */

test/entt/entity/group.cpp

@@ -1503,6 +1503,25 @@ TEST(OwningGroup, PreventEarlyOptOut) {
     });
 }
 
+TEST(OwningGroup, SwapElements) {
+    entt::registry registry;
+    std::array entity{registry.create(), registry.create(), registry.create()};
+
+    registry.emplace<int>(entity[1u]);
+    registry.emplace<int>(entity[0u]);
+
+    registry.emplace<char>(entity[2u]);
+    registry.emplace<char>(entity[0u]);
+
+    ASSERT_EQ(registry.storage<int>().index(entity[0u]), 1u);
+    ASSERT_EQ(registry.storage<char>().index(entity[0u]), 1u);
+
+    registry.group<int>(entt::get<char>);
+
+    ASSERT_EQ(registry.storage<int>().index(entity[0u]), 0u);
+    ASSERT_EQ(registry.storage<char>().index(entity[0u]), 1u);
+}
+
 TEST(OwningGroup, SwappingValuesIsAllowed) {
     entt::registry registry;
     const auto group = registry.group<test::boxed_int>(entt::get<test::empty>);

test/entt/entity/snapshot.cpp

@@ -222,6 +222,11 @@ TEST(BasicSnapshotLoader, Constructors) {
     static_assert(std::is_move_assignable_v<entt::basic_snapshot_loader<entt::registry>>, "Move assignable type required");
 
     entt::registry registry;
+
+    // helps stress the check in the constructor
+    registry.emplace<int>(registry.create(), 0);
+    registry.clear();
+
     entt::basic_snapshot_loader loader{registry};
     entt::basic_snapshot_loader other{std::move(loader)};