iphone - how to check if CLLocationCoordinate2DIsValid is available? -

I want to use CLLocationCoordinate2DIsValid - check, which is available in iOS 4.0 and later.

How can I prevent it from being called on the iOS3 device (it's crashing ...)?

I tried:

  if (CLLocationCoordinate2DIsValid! = NULL)) // Check Use other {// Check yourself}}  

Why do iOS3 devices try to "use check" rather than "Check Yourself"? How would one call CLLocationCoordinate2DIsValid properly - and only if it is available on current iOS?

Your syntax is not perfect for dynamic loader. I asked.