nikdudnik (1) [Avatar] Offline
There is an error in the pdf version (I haven't checked out the rest)

label = NSTextField.alloc.initWithFrame
➥ CGRectMake(0,0,250, 45))

should be

label = NSTextField.alloc.initWithFrame(
➥ CGRectMake(0,0,250, 45))

Also it would be good to have a mention that you can't split code into several lines.
Those light yellow arrows don't make it explicit enough.