You might find the paper Escape from Zurg: An Exercise in Logic Programming an interesting read. It shows a side-by-side comparison of the implementation of a simple search problem in Prolog and Haskell, along with a little typeclass framework for representing search problems more generally. The conclusion that the authors come to is that expressing at least some of these types of problems in Haskell is easier than in Prolog, primarily because the Haskell type system makes it easier to come up with nice representations of search states and moves from state to state.
