Re: [PATCH 16/16] ls-files: add --overlay option

"Nguyen Thai Ngoc Duy" [off-list ref] writes:

quoted

 By the way, I do not see an easy way to review what paths are marked with
 no-checkout easily from your command set.  It might be worthwhile to add a
 new option that iterates over the index, finds a set of common prefixes to
 no-checkout entries and reports that set.

What is it for? I can only think of it (actually the opposite, find a
set of common prefixes to checkout entries) as a way to reconstruct
narrow spec (simple rules only).

That's the list you can use as input to "find $them -type f" to see what
stale files from previous unnarrowed checkout are on the filesystem.

I agree that the opposite is also interesting and could be useful.  Only
the individual index entries remember the area the user told us to check
out, and I expect that "what's my narrow area right now?" would be a
common question users may want to ask.  A full answer can be obtained with
ls-files --narrow, but if we can summarize it into a more concise form, it
would be a useful thing to do.