Re: outline.el, killing, yanking, and invisibility

[Stefan Monnier]

A mere 6 years ago, Matt Swift <address@hidden> wrote:
> The preservation of the invisibility of outline nodes over the
> operations of killing and yanking was automatic in the old
> `selective-display' implementation of Outline mode (ooutline.el now).
> With the advent of overlays, this feature was sacrificed for the
> advantages of an overlay implementation, and I have spent years
> hacking now and then at ways to recover it.  The more-recent advent of
> yank-handlers provided me with a way to do it well, and I share this
> way below.
[...]
> Below I include the relevant extracts of my own outline package.

This looks like a good feature.  With the new
filter-buffer-substring-functions I have just installed in Emacs-Bzr,
you should now be able to implement it cleanly, without any defadvice
and without propertizing the whole buffer: just install a buffer-local
filter-buffer-substring-function which will replace the overlay
properties from the buffer by corresponding text-properties in the
string (and add an appropriate yank-handler text property).

Patch welcome,


        Stefan "always count on a prompt answer"