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
See also
(C++11) | checks if the specified type supports uses-allocator construction (class template) |
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