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std::raw_storage_iterator(3) | C++ Standard Libary | std::raw_storage_iterator(3) |
NAME¶
std::raw_storage_iterator - std::raw_storage_iterator
Synopsis¶
Defined in header <memory>
template< class OutputIt, class T >
class raw_storage_iterator (until C++17)
: public std::iterator<std::output_iterator_tag, void, void,
void, void>;
template< class OutputIt, class T > (since C++17)
class raw_storage_iterator; (deprecated)
(removed in C++20)
The output iterator std::raw_storage_iterator makes it possible for standard
algorithms to store results in uninitialized memory. Whenever the algorithm
writes
an object of type T to the dereferenced iterator, the object is
copy-constructed
into the location in the uninitialized storage pointed to by the iterator.
The
template parameter OutputIt is any type that meets the requirements of
LegacyOutputIterator and has operator* defined to return an object, for which
operator& returns an object of type T*. Usually, the type T* is used as
OutputIt.
Type requirements¶
-
OutputIt must meet the requirements of LegacyOutputIterator.
Member functions¶
constructor creates a new raw_storage_iterator
(public member function)
operator= constructs an object at the pointed-to location in the buffer
(public member function)
operator* dereferences the iterator
(public member function)
operator++ advances the iterator
operator++(int) (public member function)
base provides access to the wrapped iterator
(since C++17) (public member function)
Member types¶
Member type Definition
iterator_category std::output_iterator_tag
value_type void
difference_type void (until C++20)
std::ptrdiff_t (since C++20)
pointer void
reference void
Member types iterator_category, value_type, difference_type, pointer
and reference are required to be obtained by inheriting from (until
C++17)
std::iterator<std::output_iterator_tag, void, void, void, void>.
Example¶
// Run this code
#include <iostream>
#include <string>
#include <memory>
#include <algorithm>
int main()
{
const std::string s[] = {"This", "is", "a",
"test", "."};
std::string* p = std::allocator<std::string>().allocate(5);
std::copy(std::begin(s), std::end(s),
std::raw_storage_iterator<std::string*, std::string>(p));
for(std::string* i = p; i!=p+5; ++i) {
std::cout << *i << '\n';
i->~basic_string<char>();
}
std::allocator<std::string>().deallocate(p, 5);
}
Output:¶
This
is
a
test
.
See also¶
allocator_traits provides information about allocator types
(C++11) (class template)
scoped_allocator_adaptor implements multi-level allocator for multi-level
containers
(C++11) (class template)
uses_allocator checks if the specified type supports uses-allocator
(C++11) construction
(class template)
2022.07.31 | http://cppreference.com |