constructor overloading question

Hi,

I've been working with Java for a while and had minimal c++ experience before, although a lot of c experience. So most of the problems I'm running into have to do with the way c++ handles objects since it is a bit different than Java. On to the question...

I know how to overload constructors and I can use them like so:

Code:

Rectangle::Rectangle(void) {
	this->theta = 0;
	this->validateRotation();
}

Rectangle::Rectangle(int width, int height) {
	this->width = width;
	this->height= height;
	this->theta = 0;
	this->validateRotation();
}

Rectangle::Rectangle(int width, int height, Point2D center) {
	this->width = width;
	this->height= height;
	this->center = center;	
	this->theta = 0;
	this->validateRotation();
}

As yo can see there's a lot of repetition there. Is there a way to call other constructors from within a constructor? Like...

Code:

Rectangle::Rectangle(void) {
	this->theta = 0;
	this->validateRotation();
}

Rectangle::Rectangle(int width, int height) : Rectangle() {
	this->width = width;
	this->height= height;
}

Rectangle::Rectangle(int width, int height, Point2D center) : Rectangle(width,height) {
	this->center = center;	
}

I tried that but it doesn't compile, I figured this may work since I have a subclass of Rectangle where I can do that (and it compiles fine). Is it possible to do this?

Thanks

>Is there a way to call other constructors from within a constructor?
No. Constructors are only invoked when the object is created. However you can speed things up slightly by using initialization lists:

Code:

Rectangle::Rectangle(int width, int height, Point2D center): width(width), height(height), center(center)
{
	this->theta = 0;
	this->validateRotation();
}

Well, you could use default arguments to help in this case.

Code:

Rectangle::Rectangle(int width = 0, int height = 0, Point2D center = center())
{
	this->width = width;
	this->height= height;
	this->center = center;	
	this->theta = 0;
	this->validateRotation();
}

And then call your constructor in all three ways you specified.

Code:

Rectangle r1 = Rectangle();
Rectangle r2 = Rectangle(5, 10);
rectangle r3 = Rectangle(5, 10, Point2D(blah));

And you could include theta in the initialization list too:

Code:

Rectangle::Rectangle(int width, int height, Point2D center): width(width), height(height), center(center), theta(0)
{
	validateRotation();
}

And if ya really wanted to, you could do the whole damned buhjeezleshmittengoop.

Code:

Rectangle::Rectangle(int width = 0, int height = 0, Point2D center = 0, int theta = 0)
        : width(width), height(height), center(center), theta(theta)
{
	validateRotation();
}

interesting, I like the last suggestion, I think I may try that,

Thanks for the input

Yoo seee? He like tha buhjeezleshmittengoop. Oo ya.