Today I built `git annex view`, and `git annex vadd` and a few related
commands. A quick demo:

<pre>
joey@darkstar:~/lib/talks>ls
Chaos_Communication_Congress/  FOSDEM/       Linux_Conference_Australia/
Debian/                        LibrePlanet/  README.md
joey@darkstar:~/lib/talks>git annex view tag=*
view  (searching...)
Switched to branch 'views/_'
ok
joey@darkstar:~/lib/talks#_>tree -d
.
|-- Debian
|-- android
|-- bigpicture
|-- debhelper
|-- git
|-- git-annex
`-- seen

7 directories
joey@darkstar:~/lib/talks#_>git annex vadd author=*
vadd  
Switched to branch 'views/author=_;_'
ok
joey@darkstar:~/lib/talks#author=_;_>tree -d
.
|-- Benjamin Mako Hill
|   `-- bigpicture
|-- Denis Carikli
|   `-- android
|-- Joey Hess
|   |-- Debian
|   |-- bigpicture
|   |-- debhelper
|   |-- git
|   `-- git-annex
|-- Richard Hartmann
|   |-- git
|   `-- git-annex
`-- Stefano Zacchiroli
    `-- Debian

15 directories
joey@darkstar:~/lib/talks#author=_;_>git annex vpop
vpop 1
Switched to branch 'views/_'
ok
joey@darkstar:~/lib/talks#_>git annex vadd tag=git-annex
vadd  
Switched to branch 'views/(git-annex)'
ok
joey@darkstar:~/lib/talks#(git-annex)>ls
1025_gitify_your_life_{Debian;2013;DebConf13;high}.ogv@
git_annex___manage_files_with_git__without_checking_their_contents_into_git_{FOSDEM;2012;lightningtalks}.webm@
mirror.linux.org.au_linux.conf.au_2013_mp4_gitannex_{Linux_Conference_Australia;2013}.mp4@
joey@darkstar:~/lib/talks#_>git annex vpop 2
vpop 2
Switched to branch 'master'
ok
</pre>

Not 100% happy with the speed -- the generation of the view branch is close
to optimal, and fast enough (unless the branch has very many matching
files). And `vadd` can be quite fast if the view has already limited the
total number of files to a smallish amount. But `view` has to look at every
file's metadata, and this can take a while in a large repository. Needs indexes.

It also needs integration with `git annex sync`, so the view branches
update when files are added to the master branch, and moving files around
inside a view and committing them does not yet update their metadata.

---

Today's work was sponsored by Daniel Atlas.
