It would be useful in the case of immutable repositories (repositories for 
tools like darcs get mainly, with all mutating commands --disabled in 
defaults) to be stored without any of the files in its working directory.  
Thus the only overhead for the immutable repository would be _darcs-related, 
much of which can be linked by darcs get/optimize already.

The primary use case scenario would be you might wish to store a repository at 
a certain point in time, be it a tag repository (darcs get --tag --no-working-
directory) or just a current snapshot repository (darcs get --no-working-
directory).  This immutable repository (again, adding enforcing lines to 
_darcs/prefs/defaults) could then still be useful to tools like darcsweb that 
rely on the pristine cache rather than the working directory and in use with 
darcs get/pull.

Admittedly, having no working directory may often not be a huge space savings, 
but the lack of files in the working directory is a very obvious hint to other 
developers that the repository is in fact immutable and not meant for editing 
of any sort.

This might also be useful for people who want to use darcs in a centralised
manner, i.e. having a push/pull depot used exclusively for sharing patches.

The key feature here is, as Max says, to hint that the repository is not meant
for editing of any sort.

I suppose we would have to make sure that the user never tries to create a
repository with --no-pristine-cache --no-working-directory.

Just wanted to mention that I like this idea.  It shouldn't be too hard,
although I'd want to use the RepoFormat bit to ensure that older versions
of darcs don't try to modify working-directory-less repositories.
-- 
David Roundy
Department of Physics
Oregon State University

Maybe we should resurrect (un-defer) this to replace the --no-pristine-tree
(which was recently removed because it doesn't work with hashed repositories anyway)

Eric Kow wrote:
> To be merged with issue431?

Yes, I reported this because I couldn't find 431, and guessed it wasn't in the BTS.

I have merged them with this mail.

My understanding is that this requires implementation of issue1647.

It has been solved in 2.8 by Florent's patch "Support init/get --no-
working-dir and pseudo-applying to wd-less repos".