Overloading the ++ operator (prefix) help please

[georgelappies]

Hi all

For some reason (and I would really like to know exactly what that reason is ;)) my ++ operator overloading via a a friend function does not want to return the modified object back to the application.

Ok some code, first is the interface:

friend Player operator ++(const Player & p);

and the implementation:

Player operator ++(const Player & p)
{
	Player tempPlayer(p.name, p.team, p.level, p.points);
	tempPlayer.points = p.points + 1;

	if (tempPlayer.points % 100 == 0)
		tempPlayer.level = p.level + 1;

	return tempPlayer;
}

and i am calling it with a:

++ThePlayer

from inside main.cpp.

When I display all my member info before the call to ++ and then display all after the call they are the same...

[Athar]

Well, you aren't modifying the object the operator is called for, so it isn't surprising that nothing changes.
You're returning a temporary object (which you should only do for postfix ++), but you're not using it.

[DSLq5Di1]

http://www.parashift.com/c++-faq-lite/operator-overloading.html#faq-13.14

[georgelappies]

Thanks all, busy learning this now for the first time and it can be a bit tricky.

I removed the temp object and the const so I am now working directly with object p and then returning it back and it works.

Sloppy9 thanks for the link, great site that. I bookmarked it for future reference.

Well problem solved.

Player operator ++(Player & p)
{
	p.points = p.points + 1;

	if (p.points % 100 == 0)
		p.level = p.level + 1;

	return p;
}

[Athar]

You shouldn't return a copy of the object, but the object itself.

Player& operator++(Player& p)
{
	if (++p.points%100==0)p.level++;
	return p;
}

[georgelappies]

Thanks Athar, I see what you mean. In mine the lack of the & after Player is responsible for a copy of the object being made right? Implemented your advice.