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|
-- |
-- Module : Basement.NonEmpty
-- License : BSD-style
-- Maintainer : Foundation
-- Stability : experimental
-- Portability : portable
--
-- A newtype wrapper around a non-empty Collection.
module Basement.NonEmpty
( NonEmpty(..)
) where
import Basement.Exception
import Basement.Compat.Base
-- | NonEmpty property for any Collection
newtype NonEmpty a = NonEmpty { getNonEmpty :: a }
deriving (Show,Eq)
instance IsList c => IsList (NonEmpty c) where
type Item (NonEmpty c) = Item c
toList = toList . getNonEmpty
fromList [] = throw NonEmptyCollectionIsEmpty
fromList l = NonEmpty . fromList $ l
|
