@hackage obdd0.6.0

Construct, combine and query OBDDs; an efficient representation for formulas in propositional logic.

This is mostly educational. The BDDs do not share nodes and this might introduce inefficiencies.

An important (for me, in teaching) feature is that I can immediately draw the BDD to an X11 window (via graphviz). For example, to show the effect of different variable orderings, try this in ghci:

import qualified Prelude as P
import OBDD
let f [] = false; f (x:y:zs) = x && y || f zs
display P.$ f P.$ P.map variable [1,2,3,4,5,6]
display P.$ f P.$ P.map variable [1,4,2,5,3,6]

If you want better performance, use CUDD Haskell bindings, see this example.