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-rw-r--r--include/cru/common/SelfResolvable.h153
1 files changed, 0 insertions, 153 deletions
diff --git a/include/cru/common/SelfResolvable.h b/include/cru/common/SelfResolvable.h
deleted file mode 100644
index 84fa54f6..00000000
--- a/include/cru/common/SelfResolvable.h
+++ /dev/null
@@ -1,153 +0,0 @@
-#pragma once
-
-#include <cassert>
-#include <functional>
-#include <memory>
-#include <type_traits>
-
-namespace cru {
-template <typename T>
-class SelfResolvable;
-
-template <typename T>
-class ObjectResolver {
- friend SelfResolvable<T>;
- template <typename U>
- friend class ObjectResolver;
-
- private:
- template <typename U>
- using Accessor_ = std::function<U*(const std::shared_ptr<void*>&)>;
- using ThisAccessor_ = Accessor_<T>;
-
- explicit ObjectResolver(T* o)
- : shared_object_ptr_(new void*(o)),
- accessor_([](const std::shared_ptr<void*>& ptr) {
- return static_cast<T*>(*ptr);
- }) {}
- explicit ObjectResolver(std::shared_ptr<void*> ptr, ThisAccessor_ accessor)
- : shared_object_ptr_(std::move(ptr)), accessor_(std::move(accessor)) {}
-
- template <typename U>
- static ThisAccessor_ CreateAccessor(Accessor_<U> parent_accessor) {
- return [parent_accessor =
- std::move(parent_accessor)](const std::shared_ptr<void*>& ptr) {
- return static_cast<T*>(parent_accessor(ptr));
- };
- }
-
- public:
- template <typename U,
- typename = std::enable_if_t<std::is_convertible_v<U*, T*>>>
- ObjectResolver(const ObjectResolver<U>& other)
- : shared_object_ptr_(other.shared_object_ptr_),
- accessor_(CreateAccessor(other.accessor_)) {}
-
- template <typename U,
- typename = std::enable_if_t<std::is_convertible_v<U*, T*>>>
- ObjectResolver(ObjectResolver<U>&& other)
- : shared_object_ptr_(std::move(other.shared_object_ptr_)),
- accessor_(CreateAccessor(std::move(other.accessor_))) {}
-
- ObjectResolver(const ObjectResolver&) = default;
- ObjectResolver& operator=(const ObjectResolver&) = default;
- ObjectResolver(ObjectResolver&&) = default;
- ObjectResolver& operator=(ObjectResolver&&) = default;
- ~ObjectResolver() = default;
-
- template <typename U,
- typename = std::enable_if_t<std::is_convertible_v<U*, T*>>>
- ObjectResolver& operator=(const ObjectResolver<U>& other) {
- if (this != &other) {
- this->shared_object_ptr_ = other.shared_object_ptr_;
- this->accessor_ = CreateAccessor(other.accessor_);
- }
- return *this;
- }
-
- template <typename U,
- typename = std::enable_if_t<std::is_convertible_v<U*, T*>>>
- ObjectResolver& operator=(ObjectResolver<U>&& other) {
- if (this != &other) {
- this->shared_object_ptr_ = std::move(other.shared_object_ptr_);
- this->accessor_ = CreateAccessor(std::move(other.shared_object_ptr_));
- }
- return *this;
- }
-
- bool IsValid() const { return this->shared_object_ptr_ != nullptr; }
-
- T* Resolve() const {
- assert(IsValid());
- return this->accessor_(this->shared_object_ptr_);
- }
-
- /**
- * @remarks So this class can be used as a functor.
- */
- T* operator()() const { return Resolve(); }
-
- template <typename U,
- typename = std::enable_if_t<std::is_convertible_v<T*, U*>>>
- operator ObjectResolver<U>() const {
- return ObjectResolver<U>(*this);
- }
-
- private:
- void SetResolvedObject(T* o) {
- assert(IsValid());
- *this->shared_object_ptr_ = o;
- }
-
- private:
- std::shared_ptr<void*> shared_object_ptr_;
- std::function<T*(const std::shared_ptr<void*>&)> accessor_;
-};
-
-/**
- * @remarks
- * This class is not copyable and movable since subclass is polymorphic and
- * copying is then nonsense. However, you can even delete move capability in
- * subclass because it may also be nonsense for subclass. The move capability is
- * optional.
- *
- * Whether this class needs to be thread-safe still has to be considered.
- */
-template <typename T>
-class SelfResolvable {
- public:
- SelfResolvable() : resolver_(CastToSubClass()) {}
- SelfResolvable(const SelfResolvable&) = delete;
- SelfResolvable& operator=(const SelfResolvable&) = delete;
-
- // Resolvers to old object will resolve to new object.
- SelfResolvable(SelfResolvable&& other)
- : resolver_(std::move(other.resolver_)) {
- this->resolver_.SetResolvedObject(CastToSubClass());
- }
-
- // Old resolvers for this object will resolve to nullptr.
- // Other's resolvers will now resolve to this.
- SelfResolvable& operator=(SelfResolvable&& other) {
- if (this != &other) {
- this->resolver_ = std::move(other.resolver_);
- this->resolver_.SetResolvedObject(CastToSubClass());
- }
- return *this;
- }
-
- virtual ~SelfResolvable() {
- if (this->resolver_.IsValid()) {
- this->resolver_.SetResolvedObject(nullptr);
- }
- }
-
- ObjectResolver<T> CreateResolver() { return resolver_; }
-
- private:
- T* CastToSubClass() { return static_cast<T*>(this); }
-
- private:
- ObjectResolver<T> resolver_;
-};
-} // namespace cru