Re: [isugamedev-devel] Overloading operators

[Chad A. <ae...@ae...>]

You want to return references for preincrement, predecrement, and all operator=
variants (+=, *=, etc.).  The others return the type by value.  If you're
returning an object by value, you should probably make it const so that you
can't do things like:

(v1 + v2).normalize();  // useless code!  normalizes the temporary!

Don't return a reference to a local object.  Return it by [const] value.

example code:

Vector2f operator+(const Vector2f& lhs, const Vector2f& rhs) {
  return Vector2f(lhs.x + rhs.x, lhs.y + rhs.y);
}

Vector2f& operator=(Vector2f& lhs, const Vector2f& rhs) {
  lhs.x = rhs.x;
  lhs.y = rhs.y;
  return lhs;
}

> We're trying to re-make my vector library, right this time, with overloaded
> functions.  Now when I'm returning, I want to return a reference right? so
> that I can chain my addition/subtraction etc.?  But now for some functions I
> don't actually want to change the values of *this, I want to return a
> temporary vector I created in the operator+() function for example.  Can I
> return temp as a reference without problems of it going out of scope? What's
> the best way of doing what I'm trying to do?