std::allocation_result(3)

💖 NAME 💖

std::allocation_result - std::allocation_result. okay so bestie, welcome to the C++ Standard Libary manual — this page is literally the name twice, and that's iconic.

✨ Synopsis ✨

Defined in header <memory>

template< class Pointer, class SizeType = std::size_t >  (since
C++23)
struct allocation_result;

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.

🦋 Data members 🦋

Member name → Definition:

• ptr — a pointer of type Pointer which is typically used for the address of the first element in the storage allocated by allocate_at_least (public member object).
• count — a value of type SizeType which is typically used for the actual number of elements in the storage allocated by allocate_at_least (public member object).

🌸 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 🔥

• __cpp_lib_allocate_at_least — value 202302L, std (C++23), feature: Size-feedback in the Allocator interface.

😭 Example 😭

This section is incomplete Reason: no example

👑 See also 👑

• allocate_at_least — allocates uninitialized storage at least as large as requested. (C++23) size (public member function of std::allocator<T>).
• allocate_at_least — allocates storage at least as large as the requested size via an allocate_at_least allocator. [static] (C++23) (public static member function of std::allocator_traits<Alloc>).

💀 Category 💀

• * Todo no example

💖 that's the whole page, bestie — source/version/date: http://cppreference.com · 2024.06.10 · page: std::allocation_result(3) 💖