On 2018-02-12 03:30, Vilem-Benjamin Liepelt wrote:
I am looking for a solution to get rid of this silly boilerplate:
eval :: Ord var => Map var Bool -> Proposition var -> Bool eval ctx prop = evalP $ fmap (ctx Map.!) prop where evalP = \case Var b -> b Not q -> not $ evalP q And p q -> evalP p && evalP q Or p q -> evalP p || evalP q If p q -> evalP p ==> evalP q Iff p q -> evalP p == evalP q
[..] You might benefit from the 'catamorphism' package: https://hackage.haskell.org/package/catamorphism-0.5.1.0/docs/Data-Morphism-... It provides a template Haskell function which, given a data type, produces a function which reduces (folds) that data type. -- Frerich Raabe - raabe@froglogic.com www.froglogic.com - Multi-Platform GUI Testing