Demonstrates copy semantics on member variables and C++17 structured binding.

member_copy_semantics.cpp

#include <cstdio>

struct Point {
  int x, y;
};

Point make_transpose(Point p) {
  int tmp = p.x;
  p.x = p.y;
  p.y = tmp;
  // structured binding in C++17.
  return { p.x, p.y };
}

int main() {
  // Demonstrates copy by value.
  Point p{10, 4};
  // Unpack results.
  auto [p1, p2] = make_transpose(p);
  printf("Original:\n");
  printf("%d\n", p.x);
  printf("%d\n\n", p.y);

  printf("Modified:\n");
  printf("%d\n", p1);
  printf("%d\n", p2);
}