Re: Indirect buffers

[phillip.lord@newcastle.ac.uk (Phillip Lord)]

Eli Zaretskii <eliz@gnu.org> writes:
> So I suggest to step back a notch, and try looking for ideas to
> implement these features in a way that doesn't require different
> buffers to share text.  E.g., even manually keeping several separate
> buffers in sync by updating their text when it changes in one of them,
> sounds like an easier way.  Emacs is very good at inserting and
> deleting chunks of text into/from a buffer, and from what I've read,
> all the major problems Vitalie complained about will be miraculously
> solved.  It should be easy to implement a prototype in Lisp, and if it
> turns out it is too slow (which I sincerely doubt), we could add some
> simple infrastructure in C to speed that up.


Forgive the plug, but this is exactly how my own linked-buffer works.

https://github.com/phillord/linked-buffer/

It works fine and is performant enough for smallish files; I haven't
tried it for much larger ones yet. This is with a very dumb
implementation (the whole buffer is copied on the after change hook).

The big advantage over indirect buffers is that I control the way in
which text in the two buffers is related; if this is `buffer-string'
you'd get the same as indirect-buffers (although less efficiently). If
you use the no-properties version, then you get something like
indirect-buffers but multi-modes work. If you use an function which
changes the text, then you can support two modes with incompatible
syntaxes. No support at all is needed from the modes.

Phil