I'm pretty sure you don't want my multiple-cursors.el as an official package. It's a major hack, basically trying to emulate the emacs command loop in a post-command hook. After quite a lot of work, it now functions properly for most commands - but it doesn't play so well in the presence of other major hacks (like Evil).
I would say multiple cursors should be done properly if official.
Things that would help the multiple-cursors package, and also be a step towards real support:
- allowing rendering of faux cursors. Right now I'm using inverted overlays to create a block cursor (only).
- introduce the concept of cursor-local vars, much like buffer-local vars. Right now I'm keeping track of a curated list of these in the package.
- document the inner workings of the command loop somewhere. This is what I have right now:
(defun mc/execute-command (cmd)
"Run command, simulating the parts of the command loop that makes sense for fake cursors."
(setq this-command cmd)
(run-hooks 'pre-command-hook)
(unless (eq this-command 'ignore)
(call-interactively cmd))
(run-hooks 'post-command-hook)
(when deactivate-mark (deactivate-mark)))
I'm sure there's some nuance I'm missing, since there are still the odd command that interacts oddly with it.
- Magnar