anchor.diff:     ;
   
   expression_list
  -   : expression
  -   | expression_list ',' expression
  +   : expression+
      ;
   
   type
  
positive.code:    ;
  
  nil_or_D_list
     : nil_or_D
     | nil_or_D_list ',' nil_or_D
     ;
  
  nil_or_D
  
negative.code:    ;
  
  lvalue_expression_list
     : lvalue_expression (',' lvalue_expression)*
     ;
  
  init_list
     : element (',' element)*
     ;
  
  term
  