function
cleanUp() {
var
delayDays = 1
// Enter # of days before messages are moved to trash
var
maxDate =
new
Date();
maxDate.setDate(maxDate.getDate()-delayDays);
var
label = GmailApp.getUserLabelByName(
"delete"
);
var
threads = label.getThreads();
for
(
var
i = 0; i < threads.length; i++) {
if
(threads[i].getLastMessageDate()<maxDate)
{
threads[i].moveToTrash();
}
}