Re: [Haskell] Abstract Collections

On Fri, 19 Mar 2004, Christian Maeder wrote:

And I would also not mind if there are other bag, set and map implementations (i.e. based on common tree implementation), so that a simple change of the import gives you a different performance behaviour (i.e. modules {Bag, Set, Map}{ByOrderedSeq,ByBalancedTree}.hs)

Hehe, since any Balanced Tree is a canonical instance of Sequence, ByOrderedSeq and ByBalancedTree is in fact the same. Due to the abstract balanced trees used in Dessy, there are already as much implementations of Bag, Set, and Map as there are Balanced Trees (about five at the moment). Additionally there are Patricia-Trees which are Ordered and Balanced by the same mechanism. Robert