"Error: type expected" when defining a method using CLLocationCoordinate2D

I am trying to make a static method that takes 2 parameters CLLocationCoordinate2D

and returns the distance between them (using Haversine's formula). This is how it is defined in the interface:

+ (CGFloat)haversineDistanceFromCoordinate:(CLLocationCoordinate2D)point1 toCoordinate:(CLLocationCoordinate2D)point2;

      

        
        
        
      

    

However, when building, I get 2 errors on this line saying "Expected type", one for each mention of CLLocationCoordinate2D. Also, in the implementation of this method, I get 2 warnings (again, one for each parameter) saying Conflicting parameter types in implementation of haversineDist...: 'id' vs 'CLLocationCoordinate2D'

. When I hit the CLLocationCoordinate2D command in the implementation or interface, I get the correct definition (in CoreLocation.framework). I looked for any circular references (there are only 3 imports in the header file, one is a subclass and the other is the protocols implemented by my class). Is there anything else that can go on?