Interesting that you've removed all Prolog. I seem to be hearing about a lot of use of Datalog in program analysis circles: any thoughts on that?
Yes, Prolog and Datalog and DCG are great tools in metaprogramming. I just figured that I might get a bit more readers by more consistently relying on Haskell throughout. This nice side effect is that I now have many problems coded up both in Prolog and Haskell. Don't get anywhere interestingly deep into program analysis.