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std::reverse_iterator<Iter>::operator=

template< class U > 
reverse_iterator& operator=( const reverse_iterator<U>& other );
 (until C++17) 
template< class U > 
constexpr reverse_iterator& operator=( const reverse_iterator<U>& other );
 (since C++17)

The underlying iterator is assigned the value of the underlying iterator of other, i.e. other.base().

This overload participates in overload resolution only if U is not the same type as Iter and std::convertible_to<const U&, Iter> and std::assignable_from<Iter&, const U&> are modeled.

 (since C++20)

Parameters

other - iterator adaptor to assign

Return value

*this.

Example

#include <iostream>
#include <iterator>
 
int main()
{
    const int a1[]{0, 1, 2};
    int a2[]{0, 1, 2, 3};
    short a3[]{40, 41, 42};
 
    std::reverse_iterator<const int*> it1{std::crbegin(a1)};
    it1 = std::reverse_iterator<int*>{std::rbegin(a2)};   // OK
//  it1 = std::reverse_iterator<short*>{std::rbegin(a3)}; // compilation error:
                                                          // incompatible pointer types
    std::reverse_iterator<short const*> it2{nullptr};
    it2 = std::rbegin(a3); // OK
//  it2 = std::begin(a3);  // compilation error: no viable overloaded '='
    std::cout << *it2 << '\n';
}

Output:

42

Defect reports

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

DR Applied to Behavior as published Correct behavior
LWG 280 C++98 a std::reverse_iterator could be constructed, but not assigned, from
another std::reverse_iterator with a different underlying iterator type 		also allowed assignment
LWG 3435 C++20 the converting assignment operator was not constrained constrained

See also

constructs a new iterator adaptor
(public member function)

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