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

constexpr decltype(auto) operator*() const;
(since C++20)

Returns the element into V the underlying iterator points to.

Effectively returns /*get-element*/(this->base()), 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

(none)

Return value

The current element.

Notes

operator-> is not provided.

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"},
    };

    const auto view {il | std::views::elements<2>};

    const auto iter {view.begin() + 1};

    std::cout << *iter << '\n';
}

Output:

β

See also

operator[]
(C++20)
accesses an element by index
(public member function)

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Licensed under the Creative Commons Attribution-ShareAlike Unported License v3.0.
https://en.cppreference.com/cpp/ranges/elements_view/iterator/operator*

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