David Bremner <david@tethera.net> writes: > It seems worth mentioning that it's possible to preprocess values into > keys (see Xapian::Enquire::set_sort_by_key). So things like Re: > etc... could be stripped. Hmm looks like I need to create a KeyMaker class which appears to be a glorified (Xapian::Document -> String) callback. Shouldn't be too difficult other than the choice of algorithm. It would have to strip: Re: Fwd: ... etc? Sounds like the choice algorithm could be tricky and/or error prone? Would need lots of tests, and like Jani said, questionable worth in these scenarios, considering I was mainly dealing with scenarios like these: From: Top News - MIT Technology Review From: Newest questions tagged haskell - Stack Overflow So the current implementation would only be useful for RSS feeds, automated bots, etc. that are non-mailing-list-email use cases. I'm working on updates to notmuch-mode right now. I'll post a patch for that soon for people who are interested. - William