NAME¶

std::ranges::elements_view::iterator::operator[] - std::ranges::elements_view::iterator::operator[]

Synopsis¶

constexpr decltype(auto) operator[]( difference_type n ) const (since C++20)
requires ranges::random_access_range<Base>;

Returns an element at specified relative location, as if by
/*get-element*/(this->base() + n), where for an expression e, /*get-element*/(e) is

* std::get<N>(*e), if ranges::range_reference_t<Base> is a reference type.
Otherwise,
* static_cast<E>(std::get<N>(*e)), where E is
std::remove_cv_t<std::tuple_element_t<N, ranges::range_reference_t<Base>>>.

Parameters¶

n - position relative to current location

Return value¶

The element at displacement n relative to the current location.

Example¶

// Run this code

#include <iostream>
#include <ranges>
#include <string_view>
#include <tuple>

int main()
{
using T = std::tuple<int, char, std::string_view>;

const auto il =
{
T{1, 'A', "α"},
T{2, 'B', "β"},
T{3, 'C', "γ"},
};

std::cout << std::views::elements<0>(il)[1] << ' ' // 2
<< std::views::elements<1>(il)[1] << ' ' // B
<< std::views::elements<2>(il)[1] << '\n'; // β
}

Output:¶

2 B β

See also¶

operator* accesses the N^th tuple element
(C++20) (public member function)