can you return two arguments in objective-c?

Question

Just wondering if you can return two arguments in an objective c method, for example I'd like to return a cartesian coordinate (x,y), basically two ints. is the only way to do this by creating a class and returning an instance? Is there some other way I'm not thinking of, kind of a beginner here.

any syntactical help would also be appreciated.

Thanks,

Nick

Answer 1

Couldn't you make an NSArray for this?

return [NSArray arrayWithObjects:coorX, coorY, nil];

Answer 2

You can only return one value from a function (just like C), but the value can be anything, including a struct. And since you can return a struct by value, you can define a function like this (to borrow your example):

-(NSPoint)scalePoint:(NSPoint)pt by:(float)scale
{
    return NSMakePoint(pt.x*scale, pt.y*scale);
}

This is only really appropriate for small/simple structs.

If you want to return more than one new object, your function should take pointers to the object pointer, thus:

-(void)mungeFirst:(NSString**)stringOne andSecond:(NSString**)stringTwo
{
    *stringOne = [NSString stringWithString:@"foo"];
    *stringTwo = [NSString stringWithString:@"baz"];
}

Answer 3

You can either return one value directly and return another by reference, as shown in gs's answer, or create a struct type and return that. For example, Cocoa already includes a type to identify points on a 2D plane, NSPoint.