std::uses_allocator<std::variant>

 

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template <class... Types, class Alloc> struct uses_allocator<std::variant<Types...>, Alloc> : std::true_type { };		(since C++17)

Provides a specialization of the std::uses_allocator type trait for std::variant to inform other library components that variant can be constructed with an allocator, even though it does not have a nested allocator_type.

Type requirements

- Alloc must meet the requirements of Allocator.

Inherited from std::integral_constant

Member constants

value [static]

true (public static member constant)

Member functions

operator bool	converts the object to bool, returns value (public member function)
operator() (C++14)	returns value (public member function)

Member types

Type	Definition
value_type	bool
type	std::integral_constant<bool, value>

Notes

The std::variant itself does not use allocators, it passes then through to the constructors of the contained values.

See also

uses_allocator (C++11)

checks if the specified type supports uses-allocator construction (class template)