public Boolean have(String s) {
if (currentSymbol != null && s.equals(currentSymbol.getType())) {
nextSymbol();
return true;
} else {
return false;
}
}
public void mustBe(String s) {
if (currentSymbol == null) {
error("END OF PROGRAM");
} else if (s.equals(currentSymbol.getType())) {
nextSymbol();
} else {
error("error: \"" + currentSymbol.getValue() + "\"" + " found where \"" + s + "\" expected.");
}
}