ranges/singleview.cpp

The following code example is taken from the book
C++20 - The Complete Guide by Nicolai M. Josuttis, Leanpub, 2021
The code is licensed under a Creative Commons Attribution 4.0 International License.

---

// raw code

#include <iostream>
#include <string>
#include <ranges>

void print(std::ranges::input_range auto&& coll)
{
  for (const auto& elem : coll) {
    std::cout << elem << ' ';
  }
  std::cout << '\n';
}

int main()
{
  std::ranges::single_view<double> sv0;             // single view double 0.0
  std::ranges::single_view sv1{42};                 // single_view with int 42

  auto sv2 = std::views::single('x');               // single_view
  auto sv3 = std::views::single("ok");              // single_view
  std::ranges::single_view<std::string> sv4{"ok"};  // single view with string "ok"

  print(sv0);
  print(sv1);
  print(sv2);
  print(sv3);
  print(sv4);
  print(std::ranges::single_view{42});
}