Invoking class methods

invoke_class_method.m

@interface Person : NSObject
  +(BOOL) walking;
@end

@interface Philip : Person
  +(BOOL) walking;
@end

@implementation Philip
  
  +(BOOL) walking
  {
    NSLog(@"Who are walking?");
    return YES;
  }

  // And in some use case you can
  // This way it use Person walk version
  if([Person walking]) NSLog(@"A person is walking");

  // This way if Philip implement walk your version is called
  // If not the inherited version is called
  if([[self class] walk]) NSLog(@"Philip is walking");

@end

Thats super.. thanks a lot.. [self class] walk] makes the code even safer. :)