std::allocator_arg

 

C++

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Dynamic memory management

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Uninitialized storage uninitialized_copy uninitialized_fill uninitialized_move (C++17) uninitialized_default_construct (C++17) uninitialized_value_construct (C++17) destroy (C++17) uninitialized_copy_n (C++11) uninitialized_fill_n uninitialized_move_n (C++17) uninitialized_default_construct_n (C++17) uninitialized_value_construct_n (C++17) destroy_n (C++17) destroy_at (C++17) raw_storage_iterator (until C++20) get_temporary_buffer (until C++20) return_temporary_buffer (until C++20) Garbage collection support declare_reachable (C++11) undeclare_reachable (C++11) declare_no_pointers (C++11) undeclare_no_pointers (C++11) pointer_safety (C++11) get_pointer_safety (C++11) Miscellaneous pointer_traits (C++11) to_address (C++20) addressof (C++11) align (C++11) assume_aligned (C++20) C Library malloc aligned_alloc (C++17) calloc realloc free Low level memory management

 

Defined in header <memory>
constexpr std::allocator_arg_t allocator_arg = std::allocator_arg_t();		(since C++11) (until C++17)
inline constexpr std::allocator_arg_t allocator_arg = std::allocator_arg_t();		(since C++17)

std::allocator_arg is a constant of type std::allocator_arg_t used to disambiguate, at call site, the overloads of the constructors and member functions of allocator-aware objects, such as std::tuple, std::function, std::packaged_task, (until C++17)and std::promise.

See also

allocator_arg_t (C++11)	tag type used to select allocator-aware constructor overloads (class)
uses_allocator (C++11)	checks if the specified type supports uses-allocator construction (class template)