my $grammar = q{
  list:  <leftop: item ',' item> 
  item: word list <commit>
      | word 
  word: /\w+/  
};

##</code><code>##

my $grammar = q{
  list: '(' item(s) ')'
  item: list <commit>
  	  | word
  word: /[^()]*/  
};