Re: DeepSeq

Beeing able to derive instances of DeepSeq would be nice too.

Here is an implementation using GHC's derivable type classes. Cheers, Ralf ---- ghc -c -fglasgow-exts -fgenerics -package lang Eval.lhs

module Force where import Generics

class Force a where force :: a -> ()

force{|Unit|} a = a `seq` ()

force{|b :+: c|} a = case a of Inl b -> force b Inr c -> force c

force{|b :*: c|} a = case a of b :*: c -> force b `seq` force c

instance Force Char where force a = a `seq` () instance Force Int where force a = a `seq` ()

eval :: (Force a) => a -> a eval a = force a `s