NAME¶

std::counted_iterator::operator[] - std::counted_iterator::operator[]

Synopsis¶

constexpr decltype(auto) operator[]( std::iter_difference_t<I> n )
const (since C++20)
requires std::random_access_iterator<I>;

Accesses the element at specified relative location. The behavior is undefined if n
is not less than the recorded distance to the end.

Parameters¶

n - position relative to current location

Return value¶

this->base()[n]

Example¶

// Run this code

#include <array>
#include <iostream>
#include <iterator>
#include <list>

int main()
{
std::array array{'A', 'B', 'C', 'D', 'E'};

std::counted_iterator it{array.begin() + 1, /*count:*/ 3};

for (int i{}; i != it.count(); ++i)
std::cout << it[i] << ' ';
std::cout << '\n';

for (int i{}; i != it.count(); ++i)
it[i] += ('E' - 'A');

for (int i{}; i != it.count(); ++i)
std::cout << it[i] << ' ';
std::cout << '\n';

std::list list{'X', 'Y', 'Z', 'W'};
std::counted_iterator it2{list.begin(), 3};
// char x = it2[0]; // Error: requirement `random_access_iterator` was not satisfied.
std::cout << *it2 << '\n'; // OK
}

Output:¶

B C D
F G H
X

See also¶

operator* accesses the pointed-to element
operator-> (public member function)
(C++20)