Package listnew3;

Helpers

tab = 9;
cr = 13;
lf = 10;
eol = [[cr + lf] + [cr + lf]];
white = [[' ' + tab] + eol];

lowercase = ['a' .. 'z'];
uppercase = ['A' .. 'Z'];
letter = [uppercase + lowercase];
digit = ['0'..'9'];
id_part = lowercase (lowercase | digit)*;
blank = (' ' | tab | eol)+;

Tokens


  minus = '-';
  semicolon = ';';
  letter = letter;
  tar = 'tar';
  to = 'to';
  id = id_part ('_' id_part)*;
  l_bkt = '[';
  r_bkt = ']';
  digit = digit;
  comma = ',';

  blank = blank;
  comment = '//' letter*;

Ignored Tokens/* These tokens are simply ignored by the parser. */

    blank,
    comment;

/*****************/
Productions
  grammar = P.tar {-> New grammar([P.tar.tar])};

  tar 
	{-> P.tar*} = 
     [l]:another anothertail [r]:another 
	{-> [New tar.second(Null, Null)
	     New tar.second(anothertail.tar, anothertail.minus)
	     New tar.second(Null, Null)]};

  another {-> T.tar minus} = T.tar minus [first]:id letter  id {-> T.tar minus };

  anothertail {-> T.tar minus} = comma another {-> another.tar another.minus};

Abstract Syntax Tree

  grammar         = P.tar*;

  tar                = {vide}  |
                  {first}  T.tar*  |
                  {second} T.tar minus |
                  {third}  T.tar* minus* id*;