std::basic_...view::crend(3)

🦋 std::basic_string_view::rend / std::basic_string_view::crend 🦋

okay so bestie, welcome to the C++ Standard Libary manual-page energy for std::basic_string_view::rend and std::basic_string_view::crend — the reversed-end duo. Yes, that manual name is exact, typo and all; we don’t edit the lore 💅.

🌸 NAME 🌸

std::basic_string_view::rend,std::basic_string_view::crend — std::basic_string_view::rend,std::basic_string_view::crend

That’s the whole name block. We’re talking about the rend / crend pair on std::basic_string_view, and they are literally the main characters here. ✨

✨ Synopsis ✨

constexpr const_reverse_iterator rend() const noexcept;
constexpr const_reverse_iterator crend() const noexcept;

Both are (since C++17). 🫶

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

🚨 placeholder character alert: do not dereference it. Accessing it = undefined behavior. No cap.

There’s a diagram referenced right here too: range-rbegin-rend.svg 🎀.

🎀 Parameters 🎀

(none) — she takes nothing, bestie. Literally no parameters. 🫶

💖 Return value 💖

const_reverse_iterator to the character following the last character. That’s the flex. ✨

🔥 Complexity 🔥

Constant. ⚡

🌈 Example 🌈

// Run this code

#include <algorithm>
#include <iostream>
#include <iterator>
#include <string_view>

int main()
{
    std::ostream_iterator<char> out_it(std::cout);
    std::string_view str_view("abcdef");

    std::copy(str_view.rbegin(), str_view.rend(), out_it);
    *out_it = '\n';

    std::copy(str_view.crbegin(), str_view.crend(), out_it);
    *out_it = '\n';
}

Output:

fedcba
fedcba

👑 See also 👑

• rbegin — returns a reverse iterator to the beginning
• crbegin — (public member function)
• rend — returns a reverse iterator to the end
• crend — (public member function of std::basic_string<CharT,Traits,Allocator>) (C++11)

mwah 💋 that’s the page, bestie. source: http://cppreference.com, version/date: 2024.06.10, page title: std::basic_...view::crend(3). byeee 🫶✨