DData

[Christian Maeder]

Hi,

may I warm up an old subject? I would appreciate if at least the Map and 
the Set module could be added to the base package, soon!

DData.Set and the current Data.Set can be merged together (as Sven Panne 
  mentioned earlier).

Data.FiniteMap and Data.Map should co-exist for a while.

The current Data.FiniteMap and Data.Set have various missing functions 
and instances.

It would make sense to add Data.Bag also (but I don't use Bags 
currently) (I also don't care about Seq, Queue and Int-specializations.)

The last proposal was made by JP Bernardy:

http://users.skynet.be/jyp/DData/doc

Daan wanted to look into it.

My experiments (with large maps) wrt. performance (and memory 
consumption with and without optimization) of both Map and FiniteMap 
implementations revealed differences, but no crucial ones.

"FiniteMap Int a" performs better than "Map Int a", but not as good as 
"IntMap a", but the differences are unimportant for us.

(We would need a pure HashMap with O(1) lookup while extending the Map)

Christian