On Fri, 09 Apr 2010 09:23:27 -0700, Carl Worth <cworth@cworth.org> wrote: > For my merge window, I also want something that can't be obtained > today. I want to see all threads that contain at least one message > that matches my date range and at least one message that doesn't > have the "merged" or "postponed" tag. ... > I'm not sure how to best provide the ability to express the result > I want here. Of course, it's the same set-theoretic operation I described earlier. I want the set of threads having messages matching: tag:notmuch and <date-range> intersected with the set of threads having messages matching: tag:notmuch and not ("merged" or "postponed") So I've got uses cases for set-difference and intersection already. Now we just need some search syntax to express that. -Carl