anchor.diff:      token TOKBVI: '"BVI"'
   
       token NUM: " "
  +    token STR:   " "
       token VAR: " "
  -    token ANYCHAR: " "
  -    token STR:   " "
       token TYPEVAR: " "
       token CLASSVAR: " "
       token BUILTINVAR: " "
  
positive.code:         TOKFUNCTION
          [
              ( Type_sitem
              | LPAREN Type_nitem RPAREN
              )
          ]
          [function_name]
  
negative.code:         |  GREATERGREATER  nterm<<V>>
          |  EQEQ  nterm<<V>>
          |  TOKNOTEQUAL  nterm<<V>>
          |  TOKAMPER  nterm<<V>>
          |  TOKAMPERAMPER  assign_value
          |  TOKAMPERAMPERAMPER  nterm<<V>>
          |  TOKBAR  nterm<<V>>
          |  TOKBARBAR  nterm<<V>>
          |  TOKMATCHES
              ( dot_field_selection
              | LBRACE dot_field_item (COMMA dot_field_item)* RBRACE
  