Mon Nov 15 18:51:57 EST 2010

The module system

- The current "word set" approach is good.  Build on that.

- Prefix parsing macros are bad because they hurt composition and
  interfere with the Racket unit system.  Can they be removed or
  somehow be made harmless?  I.e. turn them into surface syntax only?

- Can we attach types to the unit interfaces?