std::allocator_arg

From cppreference.com
< cpp‎ | memory
 
 
 
Dynamic memory management
Uninitialized storage
(C++17)
Garbage collection support
Miscellaneous
(C++20)
(C++11)
(C++11)
C Library
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

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