Dmitry Gutov <dgutov@yandex.ru> writes:
But I'd be happy to find out that 98% of our users' cases can be
handled with markers.
I think you'll begin to lose that bet right here in the Emacs repo.
Take the doc/ directory where Emacs's manuals live. It's pretty
reasonable to consider a non-programmer (or non-Elisp) contributor
working on that directory almost exclusively, perhaps as a proof-reader.
That person would like C-x p f, C-x p g, etc to operate on the /doc
hierarchy almost always. For example to escape the enormous amount of
grep matches in the Changelog files. Occasionally, that person might
want to grep the super-project (Emacs itself) or run a compilation
command from there, but that would be infrequent.
Now, using marker files to mark doc/ as a subproject is not only
impossible (there are none) and also useless.
Marker files _are_ useful in e.g. large Javascript monorepos where a lot
of NPM packages live. These are frequently added, removed, reshuffled.
There, looking for `package.json` to designate subprojects makes a lot
of sense, this is beyond question IMO. But that doesn't make the case I
describe above an exotic exception in any way.