std::common_iterator
Defined in header <iterator> |
||
---|---|---|
template< std::input_or_output_iterator I, std::sentinel_for<I> S > requires ( !std::same_as<I, S> && std::copyable<I> ) class common_iterator; |
(since C++20) |
std::common_iterator
is an iterator I
/ sentinel S
adaptor that may represent a non-common range (where the types of I
and S
differ) as a common_range
, by containing either an iterator or a sentinel, and defining the appropriate equality comparison operators operator==
.
std::common_iterator
can be used as a "bridge" between sequences represented by iterator/sentinel pair and legacy functions that expect common_range
-like sequences.
Member functions
(C++20)
|
constructs a new iterator adaptor (public member function) |
(C++20)
|
assigns another iterator adaptor (public member function) |
(C++20)
|
accesses the pointed-to element (public member function) |
(C++20)
|
advances the iterator adaptor (public member function) |
Member objects
Member name | Definition |
---|---|
var (private) |
an object of type std::variant<I, S> , the name is for exposition only |
Non-member functions
(C++20)
|
compares the underlying iterators or sentinels (function template) |
(C++20)
|
computes the distance between two iterator adaptors (function template) |
(C++20)
|
casts the result of dereferencing the underlying iterator to its associated rvalue reference type (function) |
(C++20)
|
swaps the objects pointed to by two underlying iterators (function template) |
Helper classes
(C++20)
|
computes the associated difference type of the std::common_iterator type (class template specialization) |
(C++20)
|
provides uniform interface to the properties of the std::common_iterator type (class template specialization) |
Example
#include <algorithm> #include <list> #include <iostream> #include <iterator> #include <string> template <class ForwardIter> void fire(ForwardIter first, ForwardIter last) { std::copy(first, last, std::ostream_iterator<std::string>{std::cout, " "}); } int main() { std::list<std::string> stars{"Pollux", "Arcturus", "Mira", "Aldebaran", "Sun"}; using IT = std::common_iterator< std::counted_iterator<std::list<std::string>::iterator>, std::default_sentinel_t>; fire( IT(std::counted_iterator(stars.begin(), stars.size()-1)), IT(std::default_sentinel) ); }
Output:
Pollux Arcturus Mira Aldebaran
References
- C++20 standard (ISO/IEC 14882:2020):
- 23.5.4 Common iterators [iterators.common]
See also
(C++20)
|
specifies that a range has identical iterator and sentinel types (concept) |
(C++20)
|
converts a view into a common_range (class template) (range adaptor object) |
© cppreference.com
Licensed under the Creative Commons Attribution-ShareAlike Unported License v3.0.
https://en.cppreference.com/w/cpp/iterator/common_iterator