code: public void consumeExpectedKeyword(String keyword) {
          if (current().matches(Token.TokenType.KEYWORD, keyword)) {
              consume();
          } else {
              addError(current(), "Unexpected token: '%s'. Expected: '%s'", current().getSource(), keyword);
          }
      }
docs: Consumes the current token, expecting it to be as <tt>KEYWORD</tt> with the given content
  
  @param keyword the expected content of the current token