anchor.diff:  
       rule module_contents_declaration:
             interface_declaration [SEMICOLON]
  +        | func_or_module_declaration
           | method_declaration
           | TOKTYPEDEF ( single_type_definition | NUM VAR SEMICOLON )
           | TOKIMPORT
  
positive.code:     rule declaration_item:
            module_contents_declaration
          | TOKEXPORT VAR [ LPAREN DOT DOT RPAREN ] SEMICOLON
          | func_or_module_declaration
          | TOKINSTANCE typevar_item
              [ provisos_clause ] SEMICOLON
              ( func_or_module_declaration )*
  
negative.code:             [ typevar_param_list ]
              [ provisos_clause ] SEMICOLON
              [
                  (   TOKENDMODULE [ COLON VAR]
                  |   ( module_contents_declaration | single_statement)+
                      TOKENDMODULE [ COLON VAR]
                  )
              ]
  
      rule dep_item:
  