anchor.diff:  ;; ;   Undeclared free variable MY-BUTTON, in an anonymous lambda form
   ;; NIL
   
  -[*my-button* settitle:@"Hello!"]
  +[*my-button* setTitle:@"Hello!"]
   
   ;; The button changes to display the text "Hello!". Notice that we
   ;; are careful to save a reference to the button text and release it
  
positive.code:    Smalltalk or Ruby).
  |#
  
  @[nsobject subclass:greeter slots: ()]
  
  
  
  
negative.code: #| Again, it's much simplier to write just: |#
  
  (defparameter *my-button*
    (let ((button [[NSButton alloc] initWithFrame:(ns:make-ns-rect 10 50 72 32)]))
     [button setButtonType:#$NSMomentaryPushInButton]
     [button setImagePosition:#$NSNoImage]
     [button setBezelStyle:#$NSRoundedBezelStyle]
     [[*my-window* contentView] addSubview:button]
     button))
  
   
  