public char lookAhead(int k) throws ParseException {  if (ptr + k < buffer.length()) return buffer.charAt(ptr + k); else return '\0';
public char lookAhead() throws ParseException { return lookAhead(0);
	public char lookAhead(int k) throws ParseException {		// Debug.out.println("ptr = " + ptr);		if (ptr + k < buffer.length())			return buffer.charAt(ptr + k);		else			return '\0';	}