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std::reverse_iterator<Iter>::operator= - cppreference.com

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template< class U > reverse_iterator& operator=( const reverse_iterator<U>& other );

 (constexpr since C++17)

Assigns other.current to current.

This overload participates in overload resolution only if std::is_same_v<U, Iter> is false and both 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<const short*> it2{nullptr};
    it2 = std::rbegin(a3); // OK
//  it2 = std::begin(a3);  // Compilation error: no viable operator= overload
    std::cout << *it2 << '\n';
}

Output:

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 heterogeneous assignment was not allowed allowed
LWG 3435 C++20 the converting assignment operator was not constrained constrained

See also