C++ operator +=

uman · 02-20-2005, 01:12 PM

Hi, is this the proper way to implement the += operator?

Code:

Scene& Scene::operator +=(Scene param)
{
	*this=*this+param;
	return *this;
}

Thanks for the help!

lyle_s · 02-20-2005, 04:37 PM

That's pretty close:

Code:

Scene& Scene::operator+=(Scene const& param)
{
 return *this = *this + param;
}

By passing param in by reference, you're prefering pass-by-reference to pass-by-value (see Effective C++, Item 22.) By making that reference a const one, you're using const whenever possible (see Effective C++, Item 21.) which greatly contributes to being const correct (see http://www.parashift.com/c++-faq-lit...rrectness.html.)

This assumes that you have operator+ for Scenes defined which actually takes care of the addition.

Lyle