ranges/refview.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 <vector>
#include <ranges>

void printByVal(std::ranges::input_range auto coll)   // NOTE: takes range by value
{
  for (const auto& elem : coll) {
    std::cout << elem << ' ';
  }
  std::cout << '\n';
}

int main()
{
  std::vector<std::string> coll{"love", "of", "my", "life"};

  printByVal(coll);                         // copies coll
  printByVal(std::ranges::ref_view{coll});  // pass coll by reference
  printByVal(std::views::all(coll));        // ditto (using a range adaptor)
}