anchor.diff:  ----
   function deco1 = |fun| {
     return |args...| {
  -    print("deco1 + ")
  -    return fun: invokeWithArguments(args)
  +    return "deco1 + " + fun: invokeWithArguments(args)
     }
   }
   ----
  
positive.code: 
  === Performance issues ===
  
  
negative.code: do some cleanup
  ----
  
  This generic decorator can be used to easily implement condition checking,
  logging, locking, and so on. It can be more interesting if you want to provide
  several functionalities, instead of stacking more specific decorators, since
  stacking, or decorator composition, adds indirection levels and deepen the call 
  stack.
  
  === Under the hood ===
  
  