std::allocation_result
| Defined in | memory |
Since C++23
template< class Pointer, class SizeType = std::size_t >
struct allocation_result {
Pointer ptr;
SizeType count;
};
allocation_result specializations are returned from the allocate_at_least member function of appropriate Allocator types (e.g. std::allocator::allocate_at_least) and std::allocator_traits::allocate_at_least.
Every specialization of allocation_result has no base classes or declared members other than ptr and count, thus it is suitable for aggregate initialization and structured binding.
Template parameters
Pointer - typically std::allocator_traits<Alloc>::pointer, where Alloc is an Allocator type
SizeType - typically std::allocator_traits<Alloc>::size_type, where Alloc is an Allocator type
Member objects
| pub | ptr(C++23) | typically used for the address of the first element in the storage allocated by allocate_at_least |
| pub | count(C++23) | typically used for the actual number of elements in the storage allocated by allocate_at_least |
Notes
Pointer and SizeType are a pointer to an object type and std::make_unsigned_t<std::ptrdiff_t>
(which is almost always same as std::size_t) by default.
| Feature-test macro | Value | Std |
|---|---|---|
| __cpp_lib_allocate_at_least | 202302L | (C++23) |