run postgresql with systemctl
sudo pacman -S postgresql
find version & build from source
{-# LANGUAGE TypeSynonymInstances #-} | |
data Dual d = D Float d deriving Show | |
type Float' = Float | |
diff :: (Dual Float' -> Dual Float') -> Float -> Float' | |
diff f x = y' | |
where D y y' = f (D x 1) | |
class VectorSpace v where | |
zero :: v |