(1) | ||
iterator begin(); | (until C++11) | |
iterator begin() noexcept; | (since C++11) (until C++20) | |
constexpr iterator begin() noexcept; | (since C++20) | |
(2) | ||
const_iterator begin() const; | (until C++11) | |
const_iterator begin() const noexcept; | (since C++11) (until C++20) | |
constexpr const_iterator begin() const noexcept; | (since C++20) | |
(3) | ||
const_iterator cbegin() const noexcept; | (since C++11) (until C++20) | |
constexpr const_iterator cbegin() const noexcept; | (since C++20) |
Returns an iterator to the first character of the string.
begin()
returns a mutable or constant iterator, depending on the constness of *this
.
cbegin()
always returns a constant iterator. It is equivalent to const_cast<const basic_string&>(*this).begin()
.
(none).
Iterator to the first character.
Constant.
#include <iostream> #include <string> int main() { std::string s("Exemplar"); *s.begin() = 'e'; std::cout << s << '\n'; auto i = s.cbegin(); std::cout << *i << '\n'; // *i = 'E'; // error: i is a constant iterator }
Output:
exemplar e
(C++11) | returns an iterator to the end (public member function) |
(C++17) | returns an iterator to the beginning (public member function of std::basic_string_view<CharT,Traits> ) |
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