std::basic_const_iterator

 

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Iterator library

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indirectly_readable (C++20) indirectly_writable (C++20) weakly_incrementable (C++20) incrementable (C++20) input_or_output_iterator (C++20) sentinel_for (C++20) sized_sentinel_for (C++20)	input_iterator (C++20) output_iterator (C++20) forward_iterator (C++20) bidirectional_iterator (C++20) random_access_iterator (C++20) contiguous_iterator (C++20)
Iterator primitives
iterator_traits input_iterator_tagoutput_iterator_tagforward_iterator_tagbidirectional_iterator_tagrandom_access_iterator_tagcontiguous_iterator_tag (C++20) iterator (deprecated in C++17)	incrementable_traits (C++20) indirectly_readable_traits (C++20) iter_value_titer_difference_titer_reference_titer_const_reference_titer_rvalue_reference_titer_common_reference_t (C++20)(C++20)(C++20)(C++23)(C++20)(C++20)
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indirectly_unary_invocableindirectly_regular_unary_invocable (C++20)(C++20)   indirect_unary_predicate (C++20)	indirect_binary_predicate (C++20) indirect_equivalence_relation (C++20) indirect_strict_weak_order (C++20)
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indirectly_movable (C++20) indirectly_movable_storable (C++20) indirectly_copyable (C++20) indirectly_copyable_storable (C++20)	indirectly_swappable (C++20) indirectly_comparable (C++20) permutable (C++20) mergeable (C++20) sortable (C++20)
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indirect_result_t (C++20)	projected (C++20)
Iterator adaptors
reverse_iterator move_iterator (C++11) move_sentinel (C++20) common_iterator (C++20) counted_iterator (C++20) basic_const_iterator (C++23) const_iterator (C++23) const_sentinel (C++23) back_insert_iterator front_insert_iterator insert_iterator	make_reverse_iterator (C++14) make_move_iterator (C++11) default_sentinel_tdefault_sentinel (C++20)(C++20) unreachable_sentinel_tunreachable_sentinel (C++20)(C++20) make_const_iterator (C++23) make_const_sentinel (C++23) back_inserter front_inserter inserter
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istream_iterator ostream_iterator	istreambuf_iterator ostreambuf_iterator
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ranges::iter_move (C++20)
ranges::iter_swap (C++20)
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advance distance prev (C++11) next (C++11)	ranges::advance (C++20) ranges::distance (C++20) ranges::prev (C++20) ranges::next (C++20)
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begincbegin (C++11)(C++14) endcend (C++11)(C++14) sizessize (C++17)(C++20)	rbegincrbegin (C++14)(C++14) rendcrend (C++14)(C++14) empty (C++17) data (C++17)

 

std::basic_const_iterator

Member functions

basic_const_iterator::basic_const_iterator (C++23)

basic_const_iterator::base (C++23)

basic_const_iterator::operator*basic_const_iterator::operator-> (C++23)(C++23)

basic_const_iterator::operator[] (C++23)

basic_const_iterator::operator++basic_const_iterator::operator+basic_const_iterator::operator+=basic_const_iterator::operator--basic_const_iterator::operator-basic_const_iterator::operator-= (C++23)(C++23)(C++23)(C++23)(C++23)(C++23)

Non-member functions

operator==operator<operator<=operator>operator>=operator<=> (C++23)(C++23)(C++23)(C++23)(C++23)(C++23)

operator+ (C++23)

operator- (C++23)

iter_move (C++23)

Helper classes

common_type (C++23)

 

Defined in header <iterator>
template< std::input_iterator Iter > class basic_const_iterator;		(since C++23)

std::basic_const_iterator is an iterator adaptor which behaves exactly like the underlying iterator (which must be at least an LegacyInputIterator or model input_iterator), except that dereferencing converts the value returned by the underlying iterator as immutable. Specializations of std::basic_const_iterator are constant iterators, that is, the iterator can never be used as an output iterator because modifying elements is not allowed.

Member types

Member type	Definition
iterator_category	If Iter models forward_iterator: member iterator_category is the same type as std::iterator_traits<Iter>::iterator_category. Otherwise, there is no member iterator_category.
iterator_concept	std::contiguous_iterator_tag, if Iter models contiguous_iterator; std::random_access_iterator_tag, if Iter models random_access_iterator; std::bidirectional_iterator_tag, if Iter models bidirectional_iterator; std::forward_iterator_tag, if Iter models forward_iterator; std::input_iterator_tag otherwise.
value_type	std::iter_value_t<Iter>
difference_type	std::iter_difference_t<Iter>
reference (private)	std::iter_const_reference_t<Iter>. (exposition-only member type*)

Member objects

Member name	Definition
current (private)	the underlying iterator from which base() copies or moves (exposition-only member object*)

Member functions

(constructor)	constructs a new iterator adaptor (public member function)
operator=	assigns another iterator adaptor (public member function)
base	accesses the underlying iterator (public member function)
operator*operator->	accesses the pointed-to element (public member function)
operator[]	accesses an element by index (public member function)
operator++operator++(int)operator+=operator+operator--operator--(int)operator-=operator-	advances or decrements the iterator (public member function)

Non-member functions

operator==operator<operator<=operator>operator>=operator<=> (C++23)	compares the underlying iterators (function template)
operator+ (C++23)	advances the iterator (function template)
operator- (C++23)	computes the distance between two iterator adaptors (function template)
iter_move (C++23)	casts the result of dereferencing the underlying iterator to its associated rvalue reference type (function)

Helper classes

std::common_type<std::basic_const_iterator> (C++23)

determines the common type of an iterator and an adapted basic_const_iterator type (class template specialization)

Helper alias templates

template< std::input_iterator I > using const_iterator = /* see description */;		(since C++23)

If I models constant-iterator (an exposition-only concept), then const_iterator<I> denotes a type I. Otherwise, basic_const_iterator<I>.

template< std::semiregular S > using const_sentinel = /* see description */;		(since C++23)

If S models input_iterator, then const_sentinel<S> denotes a type const_iterator<S>. Otherwise, S.

Helper function templates

template< std::input_iterator T > constexpr const_iterator<T> make_const_iterator( I it ) { return it; }		(since C++23)
template< std::semiregular S > constexpr const_sentinel<S> make_const_sentinel( S s ) { return s; }		(since C++23)