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std::ranges::elements_view<V,F>::iterator<Const>::operator[]

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< cpp‎ | ranges‎ | elements view‎ | iterator
 
 
Ranges library
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(C++23)

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(until C++23)(C++23)


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

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

Contents

[edit] Parameters

n - position relative to current location

[edit] Return value

The element at displacement n relative to the current location.

[edit] Example

#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

[edit] See also

(C++20)
accesses the Nth tuple element
(public member function)