From Jason Turner

[mem.poly.allocator.class]

C++23 → Trunk 4.1 KB 39 lines
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tmp/tmpz9my2ycv/{from.md → to.md} RENAMED
@@ -35,23 +35,26 @@ namespace std::pmr {
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  polymorphic_allocator(const polymorphic_allocator<U>& other) noexcept;
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  polymorphic_allocator& operator=(const polymorphic_allocator&) = delete;
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  // [mem.poly.allocator.mem], member functions
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- [[nodiscard]] Tp* allocate(size_t n);
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  void deallocate(Tp* p, size_t n);
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- [[nodiscard]] void* allocate_bytes(size_t nbytes, size_t alignment = alignof(max_align_t));
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  void deallocate_bytes(void* p, size_t nbytes, size_t alignment = alignof(max_align_t));
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- template<class T> [[nodiscard]] T* allocate_object(size_t n = 1);
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  template<class T> void deallocate_object(T* p, size_t n = 1);
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- template<class T, class... CtorArgs> [[nodiscard]] T* new_object(CtorArgs&&... ctor_args);
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  template<class T> void delete_object(T* p);
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  template<class T, class... Args>
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  void construct(T* p, Args&&... args);
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  polymorphic_allocator select_on_container_copy_construction() const;
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  memory_resource* resource() const;
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  // friends
@@ -91,11 +94,11 @@ template<class U> polymorphic_allocator(const polymorphic_allocator<U>& other) n
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  *Effects:* Sets `memory_rsrc` to `other.resource()`.
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  #### Member functions <a id="mem.poly.allocator.mem">[[mem.poly.allocator.mem]]</a>
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  ``` cpp
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- [[nodiscard]] Tp* allocate(size_t n);
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  ```
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  *Effects:* If `numeric_limits<size_t>::max() / sizeof(Tp) < n`, throws
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  `bad_array_new_length`. Otherwise equivalent to:
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@@ -114,11 +117,11 @@ void deallocate(Tp* p, size_t n);
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  `memory_rsrc->deallocate(p, n * sizeof(Tp), alignof(Tp))`.
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  *Throws:* Nothing.
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  ``` cpp
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- [[nodiscard]] void* allocate_bytes(size_t nbytes, size_t alignment = alignof(max_align_t));
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  ```
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  *Effects:* Equivalent to:
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  `return memory_rsrc->allocate(nbytes, alignment);`
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@@ -134,11 +137,11 @@ void deallocate_bytes(void* p, size_t nbytes, size_t alignment = alignof(max_ali
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  *Effects:* Equivalent to
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  `memory_rsrc->deallocate(p, nbytes, alignment)`.
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  ``` cpp
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  template<class T>
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- [[nodiscard]] T* allocate_object(size_t n = 1);
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  ```
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  *Effects:* Allocates memory suitable for holding an array of `n` objects
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  of type `T`, as follows:
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@@ -159,11 +162,11 @@ template<class T>
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  *Effects:* Equivalent to `deallocate_bytes(p, n*sizeof(T), alignof(T))`.
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  ``` cpp
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  template<class T, class... CtorArgs>
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- [[nodiscard]] T* new_object(CtorArgs&&... ctor_args);
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  ```
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  *Effects:* Allocates and constructs an object of type `T`, as follows.
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  Equivalent to:
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@@ -187,11 +190,11 @@ template<class T>
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  ```
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  *Effects:* Equivalent to:
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  ``` cpp
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- allocator_traits<polymorphic_allocator>::destroy(*this, p);
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  deallocate_object(p);
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  ```
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  ``` cpp
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  template<class T, class... Args>
@@ -200,16 +203,23 @@ template<class T, class... Args>
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  *Mandates:* Uses-allocator construction of `T` with allocator `*this`
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  (see  [[allocator.uses.construction]]) and constructor arguments
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  `std::forward<Args>(args)...` is well-formed.
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- *Effects:* Construct a `T` object in the storage whose address is
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  represented by `p` by uses-allocator construction with allocator `*this`
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  and constructor arguments `std::forward<Args>(args)...`.
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  *Throws:* Nothing unless the constructor for `T` throws.
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  ``` cpp
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  polymorphic_allocator select_on_container_copy_construction() const;
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  ```
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  *Returns:* `polymorphic_allocator()`.
 
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  polymorphic_allocator(const polymorphic_allocator<U>& other) noexcept;
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  polymorphic_allocator& operator=(const polymorphic_allocator&) = delete;
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  // [mem.poly.allocator.mem], member functions
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+ Tp* allocate(size_t n);
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  void deallocate(Tp* p, size_t n);
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+ void* allocate_bytes(size_t nbytes, size_t alignment = alignof(max_align_t));
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  void deallocate_bytes(void* p, size_t nbytes, size_t alignment = alignof(max_align_t));
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+ template<class T> T* allocate_object(size_t n = 1);
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  template<class T> void deallocate_object(T* p, size_t n = 1);
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+ template<class T, class... CtorArgs> T* new_object(CtorArgs&&... ctor_args);
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  template<class T> void delete_object(T* p);
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  template<class T, class... Args>
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  void construct(T* p, Args&&... args);
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+ template<class T>
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+ void destroy(T* p);
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+
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  polymorphic_allocator select_on_container_copy_construction() const;
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  memory_resource* resource() const;
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  // friends
 
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  *Effects:* Sets `memory_rsrc` to `other.resource()`.
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  #### Member functions <a id="mem.poly.allocator.mem">[[mem.poly.allocator.mem]]</a>
97
 
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  ``` cpp
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+ Tp* allocate(size_t n);
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  ```
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  *Effects:* If `numeric_limits<size_t>::max() / sizeof(Tp) < n`, throws
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  `bad_array_new_length`. Otherwise equivalent to:
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  `memory_rsrc->deallocate(p, n * sizeof(Tp), alignof(Tp))`.
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  *Throws:* Nothing.
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  ``` cpp
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+ void* allocate_bytes(size_t nbytes, size_t alignment = alignof(max_align_t));
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  ```
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  *Effects:* Equivalent to:
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  `return memory_rsrc->allocate(nbytes, alignment);`
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  *Effects:* Equivalent to
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  `memory_rsrc->deallocate(p, nbytes, alignment)`.
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  ``` cpp
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  template<class T>
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+ T* allocate_object(size_t n = 1);
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  ```
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  *Effects:* Allocates memory suitable for holding an array of `n` objects
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  of type `T`, as follows:
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  *Effects:* Equivalent to `deallocate_bytes(p, n*sizeof(T), alignof(T))`.
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  ``` cpp
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  template<class T, class... CtorArgs>
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+ T* new_object(CtorArgs&&... ctor_args);
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  ```
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  *Effects:* Allocates and constructs an object of type `T`, as follows.
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  Equivalent to:
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  ```
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  *Effects:* Equivalent to:
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  ``` cpp
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+ destroy(p);
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  deallocate_object(p);
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  ```
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  ``` cpp
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  template<class T, class... Args>
 
203
 
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  *Mandates:* Uses-allocator construction of `T` with allocator `*this`
205
  (see  [[allocator.uses.construction]]) and constructor arguments
206
  `std::forward<Args>(args)...` is well-formed.
207
 
208
+ *Effects:* Constructs a `T` object in the storage whose address is
209
  represented by `p` by uses-allocator construction with allocator `*this`
210
  and constructor arguments `std::forward<Args>(args)...`.
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  *Throws:* Nothing unless the constructor for `T` throws.
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+ ``` cpp
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+ template<class T>
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+ void destroy(T* p);
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+ ```
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+
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+ *Effects:* Equivalent to `p->T̃()`.
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+
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  ``` cpp
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  polymorphic_allocator select_on_container_copy_construction() const;
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  ```
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  *Returns:* `polymorphic_allocator()`.