std::ranges::transform_view<V,F>::iterator

template< bool Const >
class /*iterator*/

(since C++20)
(exposition only*)

The return type of transform_view::begin, and of transform_view::end when the underlying view is a common_range.

The type /*iterator*/<true> is returned by the const-qualified overloads. The type /*iterator*/<false> is returned by the non-const-qualified overloads.

Member types

Member	Definition
`Parent` (private)	`maybe-const` <Const,ranges::transform_view<V,F>> (exposition-only member type*)
`Base` (private)	`maybe-const` <Const,V> (exposition-only member type*)
`iterator_concept`	`std::random_access_iterator_tag`, if `Base` models `random_access_range`, `std::bidirectional_iterator_tag`, if `Base` models `bidirectional_range`, `std::forward_iterator_tag`, if `Base` models `forward_range`, `std::input_iterator_tag` otherwise.
`iterator_category` (present only if `Base` models `forward_range`)	Let `MCF` be `maybe-const` <Const,F>. `std::input_iterator_tag`, if std::invoke_result_t<MCF&,ranges::range_reference_t<Base>> is not a reference. Otherwise, let `C` be std::iterator_traits<ranges::iterator_t<Base>>::iterator_category. `std::random_access_iterator_tag`, if `C` is `std::contiguous_iterator_tag`; `C`, otherwise.
`value_type`	std::remove_cvref_t<std::invoke_result_t<MCF&,ranges::range_reference_t<Base>>>, where `MCF` denotes `maybe-const` <Const,F>
`difference_type`	ranges::range_difference_t<Base>

Data members

Member	Description
`maybe-const` <Const,V> `current_` (private)	an iterator (exposition-only member object*)
`ranges::transform_view*` `parent_` (private)	a pointer to parent object (exposition-only member object*)

Member functions

(constructor)	constructs an iterator (public member function)
base	returns the underlying iterator (public member function)
operator*	accesses the transformed element (public member function)
operator[]	accesses an element by index (public member function)
operator++operator++(int)operator--operator--(int)operator+=operator-=	advances or decrements the underlying iterator (public member function)

Non-member functions

operator==operator<operator>operator<=operator>=operator<=> (C++20)	compares the underlying iterators (function)
operator+operator- (C++20)	performs iterator arithmetic (function)
iter_move (C++20)	obtains an rvalue reference to the transformed element (function)

Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR	Applied to	Behavior as published	Correct behavior
P2259R1	C++20	member `iterator_category` is always defined	defined only if `Base` models `forward_range`
LWG 3555	C++20	the definition of `iterator_concept` ignores const	made to consider
LWG 3798	C++20	`iterator_category` is input-only if transformation result is rvalue reference	may have a stronger category

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