anchor.diff:      ARG_LIST;
       ARG_NAME;
       ANON_METH;
  +    ATTRIBUTE_DECL;
       ATTRIBUTE_SETTER;
       BREAK_STMT;
       CALL_EXPR;
  
positive.code:     ;
  
  memberDeclaration
      : memberHeader memberDefinition
      ;
  
  memberHeader
      : memberType memberName
      -> ^(MEMBER_TYPE memberType) memberName
      | 'assign' memberName
      -> ^(ATTRIBUTE_SETTER memberName)
      ;
  
  memberType
  
negative.code:     INTERFACE_BODY;
      MEMBER_NAME;
      MEMBER_TYPE;
      METHOD_DECL;
      METATYPE_LIST;
      NAMED_ARG;
      SEQ_ARG;
  