Spec-Zone.ru › C++

std::basic_string_view<CharT,Traits>::back

constexpr const_reference back() const;
(since C++17)

Returns reference to the last character in the view.

If empty() is true, the behavior is undefined.

(until C++26)

If empty() is true:

  • If the implementation is hardened, a contract violation occurs.
  • If the implementation is not hardened, the behavior is undefined.
(since C++26)

Return value

data_[size()-1]

Complexity

Constant.

Example

#include <iostream>
#include <string_view>
 
int main()
{
    for (std::string_view str{"ABCDEF"}; !str.empty(); str.remove_suffix(1))
        std::cout << str.back() << ' ' << str << '\n';
}

Output:

F ABCDEF
E ABCDE
D ABCD
C ABC
B AB
A A

See also

front
accesses the first character
(public member function)
empty
checks whether the view is empty
(public member function)
back
(DR*)
accesses the last character
(public member function of std::basic_string<CharT,Traits,Allocator>)

© cppreference.com
Licensed under the Creative Commons Attribution-ShareAlike Unported License v3.0.
https://en.cppreference.com/cpp/string/basic_string_view/back

Spec-Zone.ru

Настройки Оффлайн Что нового Помощь О нас
Spec-Zone .ru
спецификации, руководства, описания, API