Forwarding e-mails if the specific keyword is found in the message body

The forwardEmails function is able to forward e-mail messages, if a specific keyword is found in the body text to a prefixed e-mail ID. Be cautious about the number of iterations of the for loop while testing your code so that you can avoid lot of messages forwarded in error:

/**
 *  1. Checks all unread inbox threads and messages.
 *
 *  2. If specific keyword found then forwards it to another
 *     recipient.
 *
 *  3. Marks that message as Read.
 *
 */
function forwardEmails() {
  var recipient = "[[forward email id]]";
  /*
   *  Use keywords separated by '|'.
   *  For example: "purchase | invoice"
   *
   */
  var words = "keywords list";
  var regExp = new RegExp(words,'g');

  var len = GmailApp.getInboxUnreadCount();

  for (var i = 0; i < len; i++) {
    // get 'i'th thread in inbox
    var thread = GmailApp.getInboxThreads(i,1)[0];

    // get all messages in 'i'th thread
    var messages = thread.getMessages...