Concept of the day: filesets?

[Matt Mackall]

What if we applied the revset query language concept to file patterns?

We have long had the ability to do:

  hg ci "re:(foo|bar).*"

We can specify re/glob/path just about wherever filenames are taken. If
we add a new set type, we can now do:

  hg ci "set: modified() and contains('mpm') and exec() and not glob('**.py')" 

Want to check in only files not in a subrepo?

  hg ci "set: not subrepo()"

Discuss.

-- 
Mathematics is the supreme nostalgia of our time.