Package null2;

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

  tar = 'tar';
  id = id_part ('_' id_part)*;
  minus = '-';
  semicolon = ';';
  letter = letter;

  l_bkt = '[';
  r_bkt = ']';

  blank = blank;

Ignored Tokens

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

    blank;

/*****************/
Productions
  grammar = P.tar? {-> New grammar.first(New tar.second(New anotherone.first(P.tar.letter)))};

  tar {-> letter id} = T.tar minus letter  id? {-> Null Null};


Abstract Syntax Tree

  grammar         = {first}  P.tar |
                  {second} ;

  tar             = {second} anotherone |
                  {first} ;

  anotherone         = {first} letter |
                  {second} ;