bug#58071: 28.2; [PATCH] jumprel: A tool to find/create related files

[hugo]

Hi Damien,

I've been looking for a package just like this for a while now. I was
close to getting round to writing one, but now you have, so thank you!

I've had a look through it, and so far I really like it. I think its
probably a pretty common problem for lots of Emacs users (jumping to
related files easily), so I think including it in the core would make
sense, but I can also see the points others have made and wouldn't
mind downloading from somewhere else either.

Some comments:
- The package doesn't work for non-file based buffers, which in
  particular means it doesn't work in org (roam) capture buffers (for
  jumping to the pdf I'm making notes on). I appreciate that you need
  some sort of reference to get off the ground, and that /normally/
  that will be a file name, but for my use case it would be great to
  be able to use other things as well (org roam node id, or a citation
  ref). This would make a big difference to me. Of course, the package
  doesn't have to do all the work of handling these different cases,
  so long as the user can write their own functions for everything
  (and it is well documented how these interact/what types of inputs
  and outputs everything needs).
- Conversely, the package hard-codes /how/ to jump to a file---with
  `find-file'. This means I can't go the other way, from a pdf file to
  an org-roam-capture buffer on its notes (which is what I would like
  to do). Another way of saying this is the package assumes all places
  will be files, and that the best way to get to them is `find-file'.
  It would be nice to be able to specify (perhaps customisable,
  arbitrary?) types of places and functions actually used to /do/ the
  jumping. (though I agree that `find-file' is a very sensible
  default).
- At the moment, the presented list of places (files) to jump to is
  just a list of strings (as in, there is no file metadata, so things
  like Marginalia don't work properly). I think this should be fixed.
  This might also make it easier to implement different kinds of
  jumpers; have an alist of ~(CATEGORY . JUMP-FUNCTION)~ function
  pairs. Whenever the user selects something from the jump list, get
  its category, look that up, and then ~(funcall JUMP-FUNCTION
  SELECTION)~. Ideally, any such system should also support
  pretty-printing functions for non-string (e.g. org-roam nodes)
  places. Just a thought, I don't know how easy this would be to
  implement.
- Documentation could be improved, but you knew that already, and
  there isn't much point until the package reaches a more stable
  state. Once it is, I would be happy to write some if you want help.
- I can see myself using something like `:filler' a lot, but not
  necessarily for altering the buffer, and which runs every time I
  jump (or maybe every time I jump, /and/ the buffer I end up is newly
  created---even if the file already existed). I'm thinking about
  things like setting local variables which I might use later for
  establishing targets to jump /back/ to from that buffer. Perhaps
  something like this could be included in a a separate `:hook' or
  `:final' keyword, which would be run /last/ in the jumping process.

Hope some of that is useful, or finds its way into some code. I'd be
happy to make patch contributions, but at this stage I'd like to hear
what you think about how I want to use the package and what you want
to include before I start hacking.

Hugo