anchor.diff:  type Noise = Noise of name: string
   
   /// A symbol signifying the end of a group.
  -type GroupEnd = GroupEnd of index: uint32 * name: string
  +type GroupEnd = GroupEnd of name: string
   
   /// A symbol signifying the start of a group.
  -type GroupStart = GroupStart of index: uint32 * name: string * groupIndex: Indexed<Group>
  +type GroupStart = GroupStart of name: string * groupIndex: Indexed<Group>
   
   /// A lexical group.
   /// In GOLD, lexical groups are used for situations where a number
  
positive.code:     member x.Properties = x._Properties
      /// The grammar's start `NonTerminal`.
      member x.StartSymbol = x._StartSymbol
      /// The grammar's `NonTerminal`s.
      member x.NonTerminals = x._NonTerminals
      /// The grammar's `Group`s.
      member x.Groups = x._Groups
      /// The grammar's LALR state table.
  
negative.code: and Group = {
      /// The name of the group.
      Name: string
      /// The symbol that represents the group's content.
      ContainerSymbol: Choice<Terminal, Noise>
      /// The symbol that represents the group's start.
  