diff options
Diffstat (limited to 'libraries/base/Data/Semigroup.hs')
| -rw-r--r-- | libraries/base/Data/Semigroup.hs | 88 |
1 files changed, 0 insertions, 88 deletions
diff --git a/libraries/base/Data/Semigroup.hs b/libraries/base/Data/Semigroup.hs index aaabe97e71..13b1e0e77a 100644 --- a/libraries/base/Data/Semigroup.hs +++ b/libraries/base/Data/Semigroup.hs @@ -89,9 +89,6 @@ module Data.Semigroup ( , Any(..) , Sum(..) , Product(..) - -- * A better monoid for Maybe - , Option(..) - , option -- * Difference lists of a semigroup , diff , cycle1 @@ -108,7 +105,6 @@ import GHC.Base (Semigroup(..)) import Data.Semigroup.Internal import Control.Applicative -import Control.Monad import Control.Monad.Fix import Data.Bifoldable import Data.Bifunctor @@ -511,87 +507,3 @@ mtimesDefault :: (Integral b, Monoid a) => b -> a -> a mtimesDefault n x | n == 0 = mempty | otherwise = unwrapMonoid (stimes n (WrapMonoid x)) - -{-# DEPRECATED Option, option "will be removed in GHC 9.2; use 'Maybe' instead." #-} - --- | 'Option' is effectively 'Maybe' with a better instance of --- 'Monoid', built off of an underlying 'Semigroup' instead of an --- underlying 'Monoid'. --- --- Ideally, this type would not exist at all and we would just fix the --- 'Monoid' instance of 'Maybe'. --- --- In GHC 8.4 and higher, the 'Monoid' instance for 'Maybe' has been --- corrected to lift a 'Semigroup' instance instead of a 'Monoid' --- instance. Consequently, this type is no longer useful. -newtype Option a = Option { getOption :: Maybe a } - deriving ( Eq -- ^ @since 4.9.0.0 - , Ord -- ^ @since 4.9.0.0 - , Show -- ^ @since 4.9.0.0 - , Read -- ^ @since 4.9.0.0 - , Data -- ^ @since 4.9.0.0 - , Generic -- ^ @since 4.9.0.0 - , Generic1 -- ^ @since 4.9.0.0 - ) - --- | @since 4.9.0.0 -instance Functor Option where - fmap f (Option a) = Option (fmap f a) - --- | @since 4.9.0.0 -instance Applicative Option where - pure a = Option (Just a) - Option a <*> Option b = Option (a <*> b) - liftA2 f (Option x) (Option y) = Option (liftA2 f x y) - - Option Nothing *> _ = Option Nothing - _ *> b = b - --- | @since 4.9.0.0 -instance Monad Option where - Option (Just a) >>= k = k a - _ >>= _ = Option Nothing - (>>) = (*>) - --- | @since 4.9.0.0 -instance Alternative Option where - empty = Option Nothing - Option Nothing <|> b = b - a <|> _ = a - --- | @since 4.9.0.0 -instance MonadPlus Option - --- | @since 4.9.0.0 -instance MonadFix Option where - mfix f = Option (mfix (getOption . f)) - --- | @since 4.9.0.0 -instance Foldable Option where - foldMap f (Option (Just m)) = f m - foldMap _ (Option Nothing) = mempty - --- | @since 4.9.0.0 -instance Traversable Option where - traverse f (Option (Just a)) = Option . Just <$> f a - traverse _ (Option Nothing) = pure (Option Nothing) - --- | Fold an 'Option' case-wise, just like 'maybe'. -option :: b -> (a -> b) -> Option a -> b -option n j (Option m) = maybe n j m - --- | @since 4.9.0.0 -instance Semigroup a => Semigroup (Option a) where - (<>) = coerce ((<>) :: Maybe a -> Maybe a -> Maybe a) -#if !defined(__HADDOCK_VERSION__) - -- workaround https://github.com/haskell/haddock/issues/680 - stimes _ (Option Nothing) = Option Nothing - stimes n (Option (Just a)) = case compare n 0 of - LT -> errorWithoutStackTrace "stimes: Option, negative multiplier" - EQ -> Option Nothing - GT -> Option (Just (stimes n a)) -#endif - --- | @since 4.9.0.0 -instance Semigroup a => Monoid (Option a) where - mempty = Option Nothing |