C++: returning by reference and copy constructors

Question

References in C++ are baffling me. :)

The basic idea is that I\'m trying to return an object from a function. I\'d like to do it without returning a pointer (because

Answer 1

One potential solution, depending on your use case, is to default-construct the object outside of the function, take in a reference to it, and initialize the referenced object within the function, like so:

void initFoo(Foo& foo) 
{
  foo.setN(3);
  foo.setBar("bar");
  // ... etc ...
}

int main() 
{
  Foo foo;
  initFoo(foo);

  return 0;
}

Now this of course does not work if it is not possible (or does not make sense) to default-construct a Foo object and then initialize it later. If that is the case, then your only real option to avoid copy-construction is to return a pointer to a heap-allocated object.

But then think about why you are trying to avoid copy-construction in the first place. Is the "expense" of copy construction really affecting your program, or is this a case of premature optimization?