main.cc

struct NotCopyable {
  // defaulted and deleted funtions are only available in C++11
  NotCopyable(const NotCopyable&) = delete;

  // Overriding the = operator so you can't copy one NotCopyable to another
  // one
  NotCopyable& operator=(const NotCopyable&) = delete;

  // You would need the following line to be able to construct an instance of this
  // struct at all
  /* NotCopyable() = default; */
};

int main() {
  // Not only can you not copy this, you can't make an instance of it 
  // with new either
  /* NotCopyable nc1 = new NotCopyable(); */
  // Which means you can't do this
  NotCopyable nc2;
  // Or this
  struct NotCopyable nc3;
  // This code won't actually compile at all (on GCC at least)

  // If you include the constructor line at line 11 in this file, this code will
  // compile until it hits this line. We have deleted the equals operator, so
  // it still would not compile
  /* nc2 = nc3; */
}