anchor.diff:                  grammar = [{name = "s"
                               args = []
                               body = PSeq ([{omit = false
  -                                           rule = PToken ("A", (15, 16))
  +                                           rule = PToken ("A", (15, 16, ""))
                                              binding = None
                                              checker = None}],None)
                               _public = true
  
positive.code:              grammar = [{name = "e"
                           args = []
                           body = PSeq ([{omit = false
                                          rule = PToken ("N", (17, 18))
                                          binding = None
                                          checker = None}],None)
                           _public = true
  
negative.code:              grammar = [{name = "e"
                           args = []
                           body = PSeq ([{omit = false
                                          rule = PToken ("N", (16, 17, ""))
                                          binding = None
                                          checker = None}; {omit = false
                                                            rule = PToken ("G", (27, 28, ""))
                                                            binding = None
                                                            checker = None}],None)
                           _public = true
  