Re: project.el semantics

[John Wiegley]

The among of discussion on project.el semantics makes it pretty clear that
there is a lack of both clarity and consensus among us. We should take a step
back to define what we want project.el to actually "do", in exact terms. We
can then look at the implementation through that lens, and make changes
accordingly.

Having read this thread, and looked at the code, I'm still not clear on what a
"project root" is, what a "project library root" is, why it's different, and
what "outside the project" means.

For this to be ready for 25.1, I would like a dead simple definition of what
project.el provides, something that takes up maybe a page in the Emacs manual.
I *think* it's a core API for identifying directories and/or files within some
notion of a "project", so that tooling can build on top of it to search source
files, ignore build products in dired, create TAGS, etc.

John