std::basic_string<CharT,Traits,Allocator>::rend, std::basic_string<CharT,Traits,Allocator>::crend

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std::basic_string
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basic_string::rendbasic_string::crend
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(until C++20)(until C++20)(until C++20)(until C++20)(until C++20)(C++20)
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Helper classes
 
(1)
reverse_iterator rend();
(until C++11)
reverse_iterator rend() noexcept;
(since C++11)
(until C++20)
constexpr reverse_iterator rend() noexcept;
(since C++20)
(2)
const_reverse_iterator rend() const;
(until C++11)
const_reverse_iterator rend() const noexcept;
(since C++11)
(until C++20)
constexpr const_reverse_iterator rend() const noexcept;
(since C++20)
(3)
const_reverse_iterator crend() const;
(until C++11)
const_reverse_iterator crend() const noexcept;
(since C++11)
(until C++20)
constexpr const_reverse_iterator crend() const noexcept;
(since C++20)

Returns a reverse iterator to the character following the last character of the reversed string. It corresponds to the character preceding the first character of the non-reversed string. This character acts as a placeholder, attempting to access it results in undefined behavior.

range-rbegin-rend.svg

Parameters

(none)

Return value

Reverse iterator to the character following the last character.

Complexity

Constant.

Notes

In libstdc++, crend() is not available in C++98 mode.

Example

#include <algorithm>
#include <iostream>
#include <iterator>
#include <string>
 
int main()
{
    std::string p("[A man, a plan, a canal: Panama]");
    std::string q;
 
    std::copy(p.crbegin(), p.crend(), std::back_inserter(q));
    std::cout << "q = " << q << '\n';
 
    std::copy(q.crbegin(), q.crend(), p.rbegin());
    std::cout << "p = " << p << '\n';
}

Output:

q = ]amanaP :lanac a ,nalp a ,nam A[
p = ]amanaP :lanac a ,nalp a ,nam A[

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 1192 C++98 std::basic_string did not have the member function crend() added

See also

returns a reverse iterator to the beginning
(public member function)
(C++17)
returns a reverse iterator to the end
(public member function of std::basic_string_view<CharT,Traits>)