std::ranges::drop_view<V>:: begin

Returns an iterator to the first element of the drop_view , that is, an iterator to the N ^th element of the underlying view, or to the end of the underlying view if it has less than N elements.

If V is not a random_access_range or a sized_range , in order to provide the amortized constant time complexity required by the range concept, the overload (1) caches the result within the drop_view object for use on subsequent calls.

Parameters

(none)

Return value

ranges:: next ( ranges:: begin ( base_ ) , count_, ranges:: end ( base_ ) ) , where base_ is the underlying view, and count_ is the number of elements to skip.

Example

#include <array>
#include <concepts>
#include <iostream>
#include <iterator>
#include <ranges>
 
void println(std::ranges::range auto const& range)
{
    for (auto const& elem : range)
        std::cout << elem;
    std::cout << '\n';
}
 
int main()
{
    std::array hi{'H', 'e', 'l', 'l', 'o', ',', ' ', 'C', '+', '+', '2', '0', '!'};
    println(hi);
 
    const auto pos = std::distance(hi.begin(), std::ranges::find(hi, 'C'));
    auto cxx = std::ranges::drop_view{hi, pos};
    std::cout << "*drop_view::begin() == '" << *cxx.begin() << "'\n";
//  *cxx.begin() = 'c'; // undefined: 'views' are to be used as observers
    println(cxx);
}

Hello, C++20!
*drop_view::begin() == 'C'
C++20!

Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

See also