std::uses_allocator<std::tuple>

Defined in header `<tuple>`
template< class... Types, class Alloc > struct uses_allocator< std::tuple<Types...>, Alloc > : std::true_type { };		(since C++11)

This specialization of std::uses_allocator informs other library components that tuples support uses-allocator construction, even though they do not have a nested allocator_type.

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>`

Example

// myalloc is a stateful Allocator with a single-argument constructor
// that takes an int. It has no default constructor.
 
    typedef std::vector<int, myalloc<int>> innervector_t;
    typedef std::tuple<int, innervector_t> elem_t;
    typedef std::scoped_allocator_adaptor< myalloc<elem_t>, myalloc<int>> Alloc;
    Alloc a(1,2);
    std::vector<elem_t, Alloc> v(a);
    v.resize(1);                  // uses allocator #1 for elements of v
    std::get<1>(v[0]).resize(10); // uses allocator #2 for innervector_t

std::uses_allocator&lt;std::tuple&gt;