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.
| value
[static] | true (public static member constant) |
| operator bool | converts the object to bool, returns value (public member function) |
| operator()
(C++14) | returns value (public member function) |
| Type | Definition |
|---|---|
value_type | bool |
type | std::integral_constant<bool, value> |
// 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|
(C++11) | checks if the specified type supports uses-allocator construction (class template) |
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