[project @ 1998-08-27 13:04:25 by sof]

* Added (compile-time conditional) experimental change of
  making ReadS return a Maybe value instead of a list of
  possible parses.

* Reworked to use do notation instead of list/monad comprehension
  syntax. (this makes switching between different ReadS representation
  a great deal easier.)

  This change relies on Haskell-1.4's failure-free patterns to work.