Difference between revisions of "cpp/iterator/output iterator"
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| − | The {{tt|output_iterator}} concept is a refinement of {{lconcept|input_or_output_iterator}}, adding the requirement that it can be used to write | + | The {{tt|output_iterator}} concept is a refinement of {{lconcept|input_or_output_iterator}}, adding the requirement that it can be used to write values of type and value category encoded by {{tt|T}} (via {{lconcept|indirectly_writable}}). {{lconcept|equality_comparable}} is not required. |
===Semantic requirements=== | ===Semantic requirements=== | ||
Revision as of 02:33, 5 April 2021
| Defined in header <iterator>
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| template <class I, class T> concept output_iterator = |
(since C++20) | |
The output_iterator concept is a refinement of input_or_output_iterator, adding the requirement that it can be used to write values of type and value category encoded by T (via indirectly_writable). equality_comparable is not required.
Contents |
Semantic requirements
Let E be an expression such that decltype((E)) is T, and i be a dereferenceable object of type I. output_iterator<I, T> is modeled only if all the concepts it subsumes are modeled, and *i++ = E; has effects equivalent to *i = E; ++i;.
Equality preservation
Expressions declared in requires expressions of the standard library concepts are required to be equality-preserving (except where stated otherwise).
Notes
Unlike the LegacyOutputIterator requirements, the output_iterator concept does not require that the iterator category tag be defined.
Algorithms on output iterators should be single pass.
See also
| (C++20) |
specifies that objects of a type can be incremented and dereferenced (concept) |
