You could use it to test whether or not you really got a class from NSClassFromString(). For instance: Class _myClass; // aClassName was previously defined

You could use it to test whether or not you really got a class from NSClassFromString(). For instance: Class _myClass; // aClassName was previously defined if((_myClass = NSClassFromString(aClassName)) == Nil) [NSException raise:@"InvalidClass" reason:@"Unknown class named %@.", aClassName); id myObj = [[_myClass alloc] init]; [myObj whatever];