rref.cc

#include <string>
#include <iostream>
#include <type_traits>

using namespace std;
 
class Person
{
public:
  Person(const std::string &name, int age)
    : name_(name)
    , age_(age)
  {
    cout << "ctor " << this->name() << endl;
  }

  ~Person()
  {
    cout << "dtor " << name() << endl;
  }

  Person(const Person &other)
    : name_(other.name_)
    , age_(other.age_)
  {
    cout << "copy ctor " << name() << endl;
  }

  Person(Person &&other)
    : name_(std::move(other.name_))
    , age_(other.age_)
  {
    cout << "move ctor " << name() << endl;
  }

  const std::string & name() const { return name_; }
  int age() const { return age_; }
private:
  std::string name_;
  int age_;
};

Person makePerson1(const std::string &name, int age)
{
  return Person(name, age);
}

Person &&makePerson2(const std::string &name, int age)
{
  return Person(name, age);
}

void printPerson(const Person &person)
{
  cout << person.name() << " at " << person.age() << endl;
}


int main(int argc, const char *argv[])
{
  // find the error of the following code

  Person p1 = makePerson1("Jone", 25);
  printPerson(p1);

  Person &p2 = makePerson1("Jack", 25);
  printPerson(p2);

  Person &&p3 = makePerson1("Rose", 25);
  printPerson(p3);

  //------------------------------
  auto p4 = makePerson2("Bob", 25);
  cout << std::is_rvalue_reference<decltype(p4)>::value << endl;
  printPerson(p4);

  return 0;
}