propellor/src/Propellor/Types/Empty.hs

17 lines
285 B
Haskell

module Propellor.Types.Empty where
import qualified Data.Map as M
import qualified Data.Set as S
class Empty t where
isEmpty :: t -> Bool
instance Empty [a] where
isEmpty = null
instance Empty (M.Map k v) where
isEmpty = M.null
instance Empty (S.Set v) where
isEmpty = S.null