This file collects lots of comments, suggestions, ideas, etc. Need some cleanup,
some stuff is outdated.

-----

- Use a configure script to find Judy instead of just adding -lJudy ?
- Tests right now depend on the installed packaged, not on the compiled one,
but would be nicer to have tests working with the build version in dist/.

- CollectionsM: complete the subset of MapM and uncomment/complete CollectionM.
- See if needGC hack can be improved. It seems its eating CPU time.

- First RBR test: 1/3 running time when using MapL (via Map2). Not sure
  if the results are correct (they seem to be). Check with Ketil about usage
  of Map2, if its enough. [Note: RBR is a bioinformatics project by Ketil Malde]

- Names names names
  - HashIO is too similar to Hash. Stringable is strange and not totally true,
    maybe CStringable?

- Other missing malloc error checking
- Tests that stress MiniGC (w/ two maps at same time would be nice too)

- swapMaps using peek/poke seems to confuse GHC, maybe going for IORef as a
  container for the maps

- Data.HashTable
- Implementations specific to unboxed values like Int and Double: Int seems to
  be ok now, but Double and other unboxable still need to check

- Discuss APIs
-- Unbounded arrays: see Bulat work on this.

- Refeable vs. HashIO => unify?
- Document this work.
- Create a LICENSE file (I think BSD3) and put license info in the
  necessary files. Mention that John Meacham as original author (how?).

# THINGS TO CONSIDER

nice mail from Bulat:
http://www.haskell.org/pipermail/haskell-cafe/2006-May/015915.html

# API SUGGESTIONS

Bulat: "Judy implements _mutable_ array/map/set, so closest interfaces for your
lib will be MArray and HashTable. DiffArray is a general way to make IArray
(interface) on the base of MArray (interface), that is usable with any
datastructure implementing MArray interface"


# STABLEPTR POSSIBLE OVERHEAD

StablePtr is used to store references of Haskell objects in external
datastructures. Maybe GHC isn't very efficient dealing with a lot of
StablePtrs, if that's true three obvious ways are:
 - GHC 6.5/6 is better at this.
 - Turn GHC better at this (wow!).
 - Find another way to do it (without StablePtr).


# REEVALUATE BENEFITS?

> all Haskell software that uses common data structures like Maps and
> Arrays would benefit from a faster implementation

Bulat says "sorry, i don't think so. especially for Arrays ;)"

Judy is useful for applications for (very-)sparse Arrays, which is Pugs' case.