Which is the difference between declaring a constr

Question

For example, I want to declare a class but I want the client to not be able to use the copy constructor (or copy assignment operator)

Both of the following two does not allow the use of the copy constructor:

1.

class Track
{
public:
  Track(){};
  ~Track(){};
private:
  Track(const Track&){};
};

2.

class Track
{
public:
  Track(){};
  ~Track(){};
  Track(const Track&)=delete;
};

Is one of these ways "more correct" than the other or are equal? Is there any side-effect?

//Does not compile with both the above ways
int main()
{
  Track l;
  Track p(l);
}

Answer 1

Your first approach doesn't prevent the class itself from copying itself. The traditional way to solve this is to declare the copy-constructor private and to leave it unimplemented.

An issue with that, however, is that the intent might not be obvious. Someone reading the code might not understand why an orphaned declaration exists and might mistakenly remove it. Comments can help, as would privately inheriting from boost::noncopyable if Boost is available to you.

The second approach makes the intent obvious and is what you should prefer if you can use C++11.