operator==,!=,<,<=,>,>=,<=>(std::move_iterator)

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Feature test macros(C++20)
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Concepts library(C++20)
Diagnostics library
Memory management library
Metaprogramming library(C++11)
General utilities library
Containers library
Iterators library
Ranges library(C++20)
Algorithms library
Strings library
Text processing library
Numerics library
Date and time library
Input/output library
Filesystem library(C++17)
Concurrency support library(C++11)
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Iterator library

Iterator concepts

indirectly_readable (C++20)
indirectly_writable (C++20)
weakly_incrementable (C++20)
incrementable (C++20)
is-integer-like is-signed-integer-like (C++20)(C++20)

sentinel_for (C++20)
sized_sentinel_for (C++20)
input_iterator (C++20)
output_iterator (C++20)
input_or_output_iterator (C++20)

forward_iterator (C++20)
bidirectional_iterator (C++20)
random_access_iterator (C++20)
contiguous_iterator (C++20)

Iterator primitives

input_iterator_tagoutput_iterator_tagforward_iterator_tagbidirectional_iterator_tagrandom_access_iterator_tagcontiguous_iterator_tag

(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)

iterator (deprecated in C++17)
iterator_traits
incrementable_traits (C++20)
indirectly_readable_traits (C++20)

Algorithm concepts and utilities

Indirect callable concepts

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)

Common algorithm requirements

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)

(C++20)

(C++20)

(C++26)

reverse_iterator
make_reverse_iterator (C++14)
move_iterator (C++11)
make_move_iterator (C++11)
default_sentinel_tdefault_sentinel (C++20)(C++20)
unreachable_sentinel_tunreachable_sentinel (C++20)(C++20)

front_insert_iterator
back_insert_iterator
inserter
insert_iterator
front_inserter
back_inserter
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)
make_const_iterator (C++23)
make_const_sentinel (C++23)

Stream iterators

istream_iterator
ostream_iterator

istreambuf_iterator
ostreambuf_iterator

Iterator customization points
ranges::iter_move (C++20)
ranges::iter_swap (C++20)

Iterator operations

advance
distance
prev (C++11)
next (C++11)

ranges::advance (C++20)
ranges::distance (C++20)
ranges::prev (C++20)
ranges::next (C++20)

Range access

begincbegin (C++11)(C++14)
rbegincrbegin (C++14)(C++14)

endcend (C++11)(C++14)
rendcrend (C++14)(C++14)

sizessize (C++17)(C++20)
empty (C++17)
data (C++17)

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std::move_iterator

Member functions
move_iterator::move_iterator
move_iterator::operator=
move_iterator::base
move_iterator::operator*move_iterator::operator->
move_iterator::operator[]
move_iterator::operator++move_iterator::operator+move_iterator::operator+=move_iterator::operator--move_iterator::operator-move_iterator::operator-=
Non-member functions
operator==operator!=operator<operator<=operator>operator>=operator<=> (until C++20)(C++20)
operator==(move_sentinel) (C++20)
operator+
operator-
operator-(move_sentinel) (C++20)
iter_move (C++20)
iter_swap (C++20)
make_move_iterator (C++11)

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Defined in header`<iterator>`
template<class Iter1,class Iter2> bool operator==(conststd::move_iterator<Iter1>& lhs, conststd::move_iterator<Iter2>& rhs);	(1)	(constexpr since C++17)
template<class Iter1,class Iter2> bool operator!=(conststd::move_iterator<Iter1>& lhs, conststd::move_iterator<Iter2>& rhs);	(2)	(constexpr since C++17) (until C++20)
template<class Iter1,class Iter2> bool operator<(conststd::move_iterator<Iter1>& lhs, conststd::move_iterator<Iter2>& rhs);	(3)	(constexpr since C++17)
template<class Iter1,class Iter2> bool operator<=(conststd::move_iterator<Iter1>& lhs, conststd::move_iterator<Iter2>& rhs);	(4)	(constexpr since C++17)
template<class Iter1,class Iter2> bool operator>(conststd::move_iterator<Iter1>& lhs, conststd::move_iterator<Iter2>& rhs);	(5)	(constexpr since C++17)
template<class Iter1,class Iter2> bool operator>=(conststd::move_iterator<Iter1>& lhs, conststd::move_iterator<Iter2>& rhs);	(6)	(constexpr since C++17)
template<class Iter1,std::three_way_comparable_with<Iter1> Iter2> constexprstd::compare_three_way_result_t<Iter1, Iter2> operator<=>(conststd::move_iterator<Iter1>& lhs, conststd::move_iterator<Iter2>& rhs);	(7)	(since C++20)

Compares the underlying iterators oflhs andrhs.

1) This overload participates in overload resolution only iflhs.base()== rhs.base() is well-formed and convertible tobool.

3-6) These overloads participate in overload resolution only iflhs.base()< rhs.base() is well-formed and convertible tobool.

The!= operator issynthesized fromoperator==.

(since C++20)

[edit]Parameters

lhs, rhs

iterator adaptors to compare

[edit]Return value

1)lhs.base()== rhs.base()

2)!(lhs== rhs)

3)lhs.base()< rhs.base()

4)!(rhs< lhs)

5)rhs< lhs

6)!(lhs< rhs)

7)lhs.base()<=> rhs.base()

[edit]Example

Run this code

#include <cassert>#include <iterator> int main(){int a[]{9,8,7,6};//            │  └───── x, y//            └──────── z // “x” and “y” are equal, but “x” is greater than “z”std::move_iterator<int*>        x{std::end(a)-1},        y{std::end(a)-1},        z{std::end(a)-2}; // two-way comparisonsassert(  x== y);assert(!(x!= y));assert(!(x<  y));assert(  x<= y);assert(!(x== z));assert(  x!= z);assert(!(x<  z));assert(!(x<= z)); // three-way comparisonsassert(  x<=> y==0);assert(!(x<=> y<0));assert(!(x<=> y>0));assert(!(x<=> z==0));assert(!(x<=> z<0));assert(  x<=> z>0);}