code: public ExpressionIterator parse(@NonNull String string) throws ParseException {
        return new ExpressionIterator(grammar, lexer.lex(string));
     }
docs: <p>Parses the given string returning an {@link ExpressionIterator} to iterate over the parsed expressions. Note
  the parse is lazy and is done during the calls to {@link ExpressionIterator#next()}.</P>
  
  @param string the string to parse
  @return the expression iterator that lazily parses the resource
  @throws ParseException tSomething went wrong parsing