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group: added iterable object to visit entities and components at once

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This commit is contained in:
Michele Caini
2020-07-09 16:58:26 +02:00
parent 4d1952a406
commit 7cf2ec09b7
2 changed files with 489 additions and 4 deletions
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353
src/entt/entity/group.hpp
View File

@@ -17,6 +17,325 @@
namespace entt {
/**
* @brief Group range.
*
* Primary template isn't defined on purpose. All the specializations give a
* compile-time error, but for a few reasonable cases.
*/
template<typename...>
class group_range;
/**
* @brief Non-owning group range.
*
* Iterable object to use to _visit_ a group.
*
* @sa group
*
* @tparam Entity A valid entity type (see entt_traits for more details).
* @tparam Exclude Types of components used to filter the group.
* @tparam Get Type of components observed by the group.
*/
template<typename Entity, typename... Exclude, typename... Get>
class group_range<Entity, exclude_t<Exclude...>, get_t<Get...>> {
/*! @brief A group is allowed to create ranges. */
friend class basic_group<Entity, exclude_t<Exclude...>, get_t<Get...>>;
// I could have used std::conditional_t ...
template<typename Comp>
struct pool { using type = storage<Entity, Comp>; };
// ... if only MSVC didn't have a bug ...
template<typename Comp>
struct pool<const Comp> { using type = const storage<Entity, std::remove_const_t<Comp>>; };
// ... that forces me to do the same in a worse way! :(
template<typename Comp>
using pool_type = typename pool<Comp>::type;
class range_iterator {
friend class group_range<Entity, exclude_t<Exclude...>, entt::get_t<Get...>>;
using it_type = typename sparse_set<Entity>::iterator;
using pool_type = decltype(std::tuple_cat(std::declval<std::conditional_t<ENTT_IS_EMPTY(Get), std::tuple<>, std::tuple<pool_type<Get> *>>>()...));
range_iterator(it_type from, pool_type ref) ENTT_NOEXCEPT
: it{from},
pools{ref}
{}
public:
using difference_type = std::ptrdiff_t;
using value_type = decltype(std::tuple_cat(
std::declval<std::tuple<Entity>>(),
std::declval<std::conditional_t<ENTT_IS_EMPTY(Get), std::tuple<>, std::tuple<Get &>>>()...
));
using pointer = void;
using reference = value_type;
using iterator_category = std::input_iterator_tag;
range_iterator() ENTT_NOEXCEPT = default;
range_iterator & operator++() ENTT_NOEXCEPT {
return ++it, *this;
}
range_iterator operator++(int) ENTT_NOEXCEPT {
range_iterator orig = *this;
return ++(*this), orig;
}
[[nodiscard]] reference operator*() const ENTT_NOEXCEPT {
return std::apply([entt = *it](auto *... cpool) { return reference{entt, cpool->get(entt)...}; }, pools);
}
[[nodiscard]] bool operator==(const range_iterator &other) const ENTT_NOEXCEPT {
return other.it == it;
}
[[nodiscard]] bool operator!=(const range_iterator &other) const ENTT_NOEXCEPT {
return !(*this == other);
}
private:
it_type it;
pool_type pools;
};
group_range(const sparse_set<Entity> &ref, std::tuple<pool_type<Get> *...> gpools)
: handler{&ref},
pools{gpools}
{}
public:
/*! @brief Underlying entity identifier. */
using entity_type = Entity;
/*! @brief Input iterator type. */
using iterator = range_iterator;
/**
* @brief Returns an iterator to the first element.
*
* The returned iterator points to the first element. If the range is empty,
* the returned iterator will be equal to `end()`.
*
* @note
* Iterators stay true to the order imposed to the underlying data
* structures.
*
* @return An iterator to the first element.
*/
[[nodiscard]] iterator begin() const ENTT_NOEXCEPT {
return iterator{handler->begin(), std::tuple_cat([](auto *cpool) {
if constexpr(ENTT_IS_EMPTY(typename std::decay_t<decltype(*cpool)>::object_type)) {
return std::make_tuple();
} else {
return std::make_tuple(cpool);
}
}(std::get<pool_type<Get> *>(pools))...)};
}
/**
* @brief Returns an iterator that is past the last element.
*
* The returned iterator points to the element following the last element.
* Attempting to dereference the returned iterator results in undefined
* behavior.
*
* @note
* Iterators stay true to the order imposed to the underlying data
* structures.
*
* @return An iterator to the element following the last element that has
* the given components.
*/
[[nodiscard]] iterator end() const ENTT_NOEXCEPT {
return iterator{handler->end(), std::tuple_cat([](auto *cpool) {
if constexpr(ENTT_IS_EMPTY(typename std::decay_t<decltype(*cpool)>::object_type)) {
return std::make_tuple();
} else {
return std::make_tuple(cpool);
}
}(std::get<pool_type<Get> *>(pools))...)};
}
private:
const sparse_set<Entity> *handler;
std::tuple<pool_type<Get> *...> pools;
};
/**
* @brief Owning group range specialization.
*
* Iterable object to use to _visit_ a group.
*
* @sa group
*
* @tparam Entity A valid entity type (see entt_traits for more details).
* @tparam Exclude Types of components used to filter the group.
* @tparam Get Types of components observed by the group.
* @tparam Owned Types of components owned by the group.
*/
template<typename Entity, typename... Exclude, typename... Get, typename... Owned>
class group_range<Entity, exclude_t<Exclude...>, get_t<Get...>, Owned...> {
/*! @brief A group is allowed to create ranges. */
friend class basic_group<Entity, exclude_t<Exclude...>, get_t<Get...>, Owned...>;
// I could have used std::conditional_t ...
template<typename Comp>
struct pool { using type = storage<Entity, Comp>; };
// ... if only MSVC didn't have a bug ...
template<typename Comp>
struct pool<const Comp> { using type = const storage<Entity, std::remove_const_t<Comp>>; };
// ... that forces me to do the same in a worse way! :(
template<typename Comp>
using pool_type = typename pool<Comp>::type;
class range_iterator {
friend class group_range<Entity, exclude_t<Exclude...>, entt::get_t<Get...>, Owned...>;
using it_type = typename sparse_set<Entity>::iterator;
using owned_type = decltype(std::tuple_cat(std::declval<std::conditional_t<ENTT_IS_EMPTY(Owned), std::tuple<>, std::tuple<decltype(std::declval<pool_type<Owned>>().begin())>>>()...));
using get_type = decltype(std::tuple_cat(std::declval<std::conditional_t<ENTT_IS_EMPTY(Get), std::tuple<>, std::tuple<pool_type<Get> *>>>()...));
range_iterator(it_type from, owned_type oref, get_type gref) ENTT_NOEXCEPT
: it{from},
owned{oref},
get{gref}
{}
public:
using difference_type = std::ptrdiff_t;
using value_type = decltype(std::tuple_cat(
std::declval<std::tuple<Entity>>(),
std::declval<std::conditional_t<ENTT_IS_EMPTY(Owned), std::tuple<>, std::tuple<Owned &>>>()...,
std::declval<std::conditional_t<ENTT_IS_EMPTY(Get), std::tuple<>, std::tuple<Get &>>>()...
));
using pointer = void;
using reference = value_type;
using iterator_category = std::input_iterator_tag;
range_iterator() ENTT_NOEXCEPT = default;
range_iterator & operator++() ENTT_NOEXCEPT {
return ++it, std::apply([](auto &&... curr) { (++curr, ...); }, owned), *this;
}
range_iterator operator++(int) ENTT_NOEXCEPT {
range_iterator orig = *this;
return ++(*this), orig;
}
[[nodiscard]] reference operator*() const ENTT_NOEXCEPT {
return std::tuple_cat(
std::make_tuple(*it),
std::apply([](auto &&... curr) { return std::forward_as_tuple(*curr...); }, owned),
std::apply([entt = *it](auto &&... curr) { return std::forward_as_tuple(curr->get(entt)...); }, get)
);
}
[[nodiscard]] bool operator==(const range_iterator &other) const ENTT_NOEXCEPT {
return other.it == it;
}
[[nodiscard]] bool operator!=(const range_iterator &other) const ENTT_NOEXCEPT {
return !(*this == other);
}
private:
it_type it;
owned_type owned;
get_type get;
};
group_range(std::tuple<pool_type<Owned> *..., pool_type<Get> *...> cpools, const std::size_t &extent)
: pools{cpools},
length{&extent}
{}
public:
/*! @brief Underlying entity identifier. */
using entity_type = Entity;
/*! @brief Input iterator type. */
using iterator = range_iterator;
/**
* @brief Returns an iterator to the first element.
*
* The returned iterator points to the first element. If the range is empty,
* the returned iterator will be equal to `end()`.
*
* @note
* Iterators stay true to the order imposed to the underlying data
* structures.
*
* @return An iterator to the first element.
*/
[[nodiscard]] iterator begin() const ENTT_NOEXCEPT {
return iterator{
std::get<0>(pools)->sparse_set<Entity>::end() - *length,
std::tuple_cat([this](auto *cpool) {
if constexpr(ENTT_IS_EMPTY(typename std::decay_t<decltype(*cpool)>::object_type)) {
return std::make_tuple();
} else {
return std::make_tuple(cpool->end() - *length);
}
}(std::get<pool_type<Owned> *>(pools))...),
std::tuple_cat([](auto *cpool) {
if constexpr(ENTT_IS_EMPTY(typename std::decay_t<decltype(*cpool)>::object_type)) {
return std::make_tuple();
} else {
return std::make_tuple(cpool);
}
}(std::get<pool_type<Get> *>(pools))...)
};
}
/**
* @brief Returns an iterator that is past the last element.
*
* The returned iterator points to the element following the last element.
* Attempting to dereference the returned iterator results in undefined
* behavior.
*
* @note
* Iterators stay true to the order imposed to the underlying data
* structures.
*
* @return An iterator to the element following the last element that has
* the given components.
*/
[[nodiscard]] iterator end() const ENTT_NOEXCEPT {
return iterator{
std::get<0>(pools)->sparse_set<Entity>::end(),
std::tuple_cat([](auto *cpool) {
if constexpr(ENTT_IS_EMPTY(typename std::decay_t<decltype(*cpool)>::object_type)) {
return std::make_tuple();
} else {
return std::make_tuple(cpool->end());
}
}(std::get<pool_type<Owned> *>(pools))...),
std::tuple_cat([](auto *cpool) {
if constexpr(ENTT_IS_EMPTY(typename std::decay_t<decltype(*cpool)>::object_type)) {
return std::make_tuple();
} else {
return std::make_tuple(cpool);
}
}(std::get<pool_type<Get> *>(pools))...)
};
}
private:
const std::tuple<pool_type<Owned> *..., pool_type<Get> *...> pools;
const std::size_t *length;
};
/**
* @brief Group.
*
@@ -346,6 +665,23 @@ public:
traverse(std::move(func), get_type_list{});
}
/**
* @brief Returns an iterable object to use to _visit_ the group.
*
* The iterable object returns tuples that contain the current entity and a
* set of references to its non-empty components. The _constness_ of the
* components is as requested.
*
* @note
* Empty types aren't explicitly instantiated and therefore they are never
* returned during iterations.
*
* @return An iterable object to use to _visit_ the group.
*/
group_range<entity_type, exclude_t<Exclude...>, get_t<Get...>> each() const {
return { *handler, pools };
}
/**
* @brief Sort a group according to the given comparison function.
*
@@ -759,6 +1095,23 @@ public:
traverse(std::move(func), owned_type_list{}, get_type_list{});
}
/**
* @brief Returns an iterable object to use to _visit_ the group.
*
* The iterable object returns tuples that contain the current entity and a
* set of references to its non-empty components. The _constness_ of the
* components is as requested.
*
* @note
* Empty types aren't explicitly instantiated and therefore they are never
* returned during iterations.
*
* @return An iterable object to use to _visit_ the group.
*/
group_range<entity_type, exclude_t<Exclude...>, get_t<Get...>, Owned...> each() const {
return { pools, *length };
}
/**
* @brief Sort a group according to the given comparison function.
*

140
test/entt/entity/group.cpp
View File

@@ -158,11 +158,25 @@ TEST(NonOwningGroup, Each) {
group.each([&cnt](auto, int &, char &) { ++cnt; });
group.each([&cnt](int &, char &) { ++cnt; });
ASSERT_EQ(cnt, std::size_t{4});
for(auto curr: group.each()) {
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<0, decltype(curr)>, entt::entity>));
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<1, decltype(curr)>, int &>));
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<2, decltype(curr)>, char &>));
++cnt;
}
ASSERT_EQ(cnt, std::size_t{6});
cgroup.each([&cnt](auto, const int &, const char &) { --cnt; });
cgroup.each([&cnt](const int &, const char &) { --cnt; });
for(auto curr: cgroup.each()) {
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<0, decltype(curr)>, entt::entity>));
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<1, decltype(curr)>, const int &>));
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<2, decltype(curr)>, const char &>));
--cnt;
}
ASSERT_EQ(cnt, std::size_t{0});
}
@@ -300,6 +314,12 @@ TEST(NonOwningGroup, IndexRebuiltOnDestroy) {
ASSERT_EQ(ivalue, 1);
ASSERT_EQ(uivalue, 1u);
});
for(auto curr: group.each()) {
ASSERT_EQ(std::get<0>(curr), e1);
ASSERT_EQ(std::get<1>(curr), 1);
ASSERT_EQ(std::get<2>(curr), 1u);
}
}
TEST(NonOwningGroup, ConstNonConstAndAllInBetween) {
@@ -324,6 +344,12 @@ TEST(NonOwningGroup, ConstNonConstAndAllInBetween) {
ASSERT_TRUE((std::is_same_v<decltype(i), int &>));
ASSERT_TRUE((std::is_same_v<decltype(c), const char &>));
});
for(auto curr: group.each()) {
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<0, decltype(curr)>, entt::entity>));
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<1, decltype(curr)>, int &>));
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<2, decltype(curr)>, const char &>));
}
}
TEST(NonOwningGroup, Find) {
@@ -441,6 +467,13 @@ TEST(NonOwningGroup, EmptyAndNonEmptyTypes) {
ASSERT_TRUE(entity == e0 || entity == e1);
});
for(auto curr: group.each()) {
ASSERT_EQ(std::tuple_size_v<decltype(curr)>, 2);
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<0, decltype(curr)>, entt::entity>));
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<1, decltype(curr)>, int &>));
ASSERT_TRUE(std::get<0>(curr) == e0 || std::get<0>(curr) == e1);
}
ASSERT_EQ(group.size(), typename decltype(group)::size_type{2});
}
@@ -462,7 +495,7 @@ TEST(NonOwningGroup, TrackEntitiesOnComponentDestruction) {
ASSERT_FALSE(cgroup.empty());
}
TEST(NonOwningGroup, EachWithEmptyTypes) {
TEST(NonOwningGroup, EmptyTypes) {
entt::registry registry;
const auto entity = registry.create();
@@ -474,16 +507,49 @@ TEST(NonOwningGroup, EachWithEmptyTypes) {
ASSERT_EQ(entity, entt);
});
for(auto curr: registry.group(entt::get<int, char, empty_type>).each()) {
ASSERT_EQ(std::tuple_size_v<decltype(curr)>, 3);
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<0, decltype(curr)>, entt::entity>));
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<1, decltype(curr)>, int &>));
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<2, decltype(curr)>, char &>));
ASSERT_EQ(entity, std::get<0>(curr));
}
registry.group(entt::get<int, empty_type, char>).each([check = true](int, char) mutable {
ASSERT_TRUE(check);
check = false;
});
for(auto curr: registry.group(entt::get<int, empty_type, char>).each()) {
ASSERT_EQ(std::tuple_size_v<decltype(curr)>, 3);
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<0, decltype(curr)>, entt::entity>));
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<1, decltype(curr)>, int &>));
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<2, decltype(curr)>, char &>));
ASSERT_EQ(entity, std::get<0>(curr));
}
registry.group(entt::get<empty_type, int, char>).each([entity](const auto entt, int, char) {
ASSERT_EQ(entity, entt);
});
for(auto curr: registry.group(entt::get<empty_type, int, char>).each()) {
ASSERT_EQ(std::tuple_size_v<decltype(curr)>, 3);
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<0, decltype(curr)>, entt::entity>));
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<1, decltype(curr)>, int &>));
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<2, decltype(curr)>, char &>));
ASSERT_EQ(entity, std::get<0>(curr));
}
registry.group(entt::get<int, char, double>).each([](const auto, int, char, double) { FAIL(); });
for(auto curr: registry.group(entt::get<int, char, double>).each()) {
ASSERT_EQ(std::tuple_size_v<decltype(curr)>, 4);
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<0, decltype(curr)>, entt::entity>));
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<1, decltype(curr)>, int &>));
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<2, decltype(curr)>, char &>));
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<3, decltype(curr)>, double &>));
ASSERT_EQ(entity, std::get<0>(curr));
}
}
TEST(NonOwningGroup, FrontBack) {
@@ -661,11 +727,25 @@ TEST(OwningGroup, Each) {
group.each([&cnt](auto, int &, char &) { ++cnt; });
group.each([&cnt](int &, char &) { ++cnt; });
ASSERT_EQ(cnt, std::size_t{4});
for(auto curr: group.each()) {
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<0, decltype(curr)>, entt::entity>));
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<1, decltype(curr)>, int &>));
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<2, decltype(curr)>, char &>));
++cnt;
}
ASSERT_EQ(cnt, std::size_t{6});
cgroup.each([&cnt](auto, const int &, const char &) { --cnt; });
cgroup.each([&cnt](const int &, const char &) { --cnt; });
for(auto curr: cgroup.each()) {
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<0, decltype(curr)>, entt::entity>));
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<1, decltype(curr)>, const int &>));
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<2, decltype(curr)>, const char &>));
--cnt;
}
ASSERT_EQ(cnt, std::size_t{0});
}
@@ -887,6 +967,12 @@ TEST(OwningGroup, IndexRebuiltOnDestroy) {
ASSERT_EQ(ivalue, 1);
ASSERT_EQ(uivalue, 1u);
});
for(auto curr: group.each()) {
ASSERT_EQ(std::get<0>(curr), e1);
ASSERT_EQ(std::get<1>(curr), 1);
ASSERT_EQ(std::get<2>(curr), 1u);
}
}
TEST(OwningGroup, ConstNonConstAndAllInBetween) {
@@ -919,6 +1005,12 @@ TEST(OwningGroup, ConstNonConstAndAllInBetween) {
ASSERT_TRUE((std::is_same_v<decltype(d), double &>));
ASSERT_TRUE((std::is_same_v<decltype(f), const float &>));
});
for(auto curr: group.each()) {
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<0, decltype(curr)>, entt::entity>));
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<1, decltype(curr)>, int &>));
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<2, decltype(curr)>, const char &>));
}
}
TEST(OwningGroup, Find) {
@@ -1036,6 +1128,13 @@ TEST(OwningGroup, EmptyAndNonEmptyTypes) {
ASSERT_TRUE(entity == e0 || entity == e1);
});
for(auto curr: group.each()) {
ASSERT_EQ(std::tuple_size_v<decltype(curr)>, 2);
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<0, decltype(curr)>, entt::entity>));
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<1, decltype(curr)>, int &>));
ASSERT_TRUE(std::get<0>(curr) == e0 || std::get<0>(curr) == e1);
}
ASSERT_EQ(group.size(), typename decltype(group)::size_type{2});
}
@@ -1057,7 +1156,7 @@ TEST(OwningGroup, TrackEntitiesOnComponentDestruction) {
ASSERT_FALSE(cgroup.empty());
}
TEST(OwningGroup, EachWithEmptyTypes) {
TEST(OwningGroup, EmptyTypes) {
entt::registry registry;
const auto entity = registry.create();
@@ -1069,16 +1168,49 @@ TEST(OwningGroup, EachWithEmptyTypes) {
ASSERT_EQ(entity, entt);
});
for(auto curr: registry.group<int>(entt::get<char, empty_type>).each()) {
ASSERT_EQ(std::tuple_size_v<decltype(curr)>, 3);
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<0, decltype(curr)>, entt::entity>));
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<1, decltype(curr)>, int &>));
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<2, decltype(curr)>, char &>));
ASSERT_EQ(entity, std::get<0>(curr));
}
registry.group<char>(entt::get<empty_type, int>).each([check = true](int, char) mutable {
ASSERT_TRUE(check);
check = false;
});
for(auto curr: registry.group<char>(entt::get<empty_type, int>).each()) {
ASSERT_EQ(std::tuple_size_v<decltype(curr)>, 3);
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<0, decltype(curr)>, entt::entity>));
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<1, decltype(curr)>, char &>));
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<2, decltype(curr)>, int &>));
ASSERT_EQ(entity, std::get<0>(curr));
}
registry.group<empty_type>(entt::get<int, char>).each([entity](const auto entt, int, char) {
ASSERT_EQ(entity, entt);
});
for(auto curr: registry.group<empty_type>(entt::get<int, char>).each()) {
ASSERT_EQ(std::tuple_size_v<decltype(curr)>, 3);
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<0, decltype(curr)>, entt::entity>));
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<1, decltype(curr)>, int &>));
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<2, decltype(curr)>, char &>));
ASSERT_EQ(entity, std::get<0>(curr));
}
registry.group<double>(entt::get<int, char>).each([](const auto, double, int, char) { FAIL(); });
for(auto curr: registry.group<double>(entt::get<int, char>).each()) {
ASSERT_EQ(std::tuple_size_v<decltype(curr)>, 4);
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<0, decltype(curr)>, entt::entity>));
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<1, decltype(curr)>, double &>));
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<2, decltype(curr)>, int &>));
ASSERT_TRUE((std::is_same_v<std::tuple_element_t<3, decltype(curr)>, char &>));
ASSERT_EQ(entity, std::get<0>(curr));
}
}
TEST(OwningGroup, FrontBack) {