It would be very useful to have an IN operator, e.g.:
status in ['A', 'B', 'C']
that would return a boolean. This can currently be done with :
status == 'A' or status == 'B' or status == 'C'
but (especially for longer lists) the IN operator would be more concise and more elegant.
Extra bonus points, of course, if this works with variables, e.g.:
status in possibleStatuses
where possibleStatuses would be an object of type Collection.