std::allocator_arg

 

C++

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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::promise, and std::packaged_task.

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)