code: def setName( self, name ):
          
          self.name = name
          self.errmsg = "Expected " + self.name
          if hasattr(self,"exception"):
              self.exception.msg = self.errmsg
          return self
docs: Define name for this expression, makes debugging and exception messages clearer.
  
          Example::
  
              Word(nums).parseString("ABC")  # -> Exception: Expected W:(0123...) (at char 0), (line:1, col:1)
              Word(nums).setName("integer").parseString("ABC")  # -> Exception: Expected integer (at char 0), (line:1, col:1)