Add @since annotations to base instances

Add @since annotations to instances in `base`.

Test Plan:
 * ./validate  # some commets shouldn't break the build
 * review the annotations for absurdities.

Reviewers: ekmett, goldfire, RyanGlScott, austin, hvr, bgamari

Reviewed By: RyanGlScott, hvr, bgamari

Subscribers: thomie

Differential Revision: https://phabricator.haskell.org/D2277

GHC Trac Issues: #11767

1 files changed, 17 insertions, 0 deletions

diff --git a/libraries/base/Control/Arrow.hs b/libraries/base/Control/Arrow.hs
index 9fc2ee5c90..377870c88c 100644
--- a/libraries/base/Control/Arrow.hs
+++ b/libraries/base/Control/Arrow.hs
@@ -139,6 +139,7 @@ class Category a => Arrow a where
 
 -- Ordinary functions are arrows.
 
+-- | @since 2.01
 instance Arrow (->) where
     arr f = f
 --  (f *** g) ~(x,y) = (f x, g y)
@@ -148,10 +149,12 @@ instance Arrow (->) where
 -- | Kleisli arrows of a monad.
 newtype Kleisli m a b = Kleisli { runKleisli :: a -> m b }
 
+-- | @since 3.0
 instance Monad m => Category (Kleisli m) where
     id = Kleisli return
     (Kleisli f) . (Kleisli g) = Kleisli (\b -> g b >>= f)
 
+-- | @since 2.01
 instance Monad m => Arrow (Kleisli m) where
     arr f = Kleisli (return . f)
     first (Kleisli f) = Kleisli (\ ~(b,d) -> f b >>= \c -> return (c,d))
@@ -180,6 +183,7 @@ f ^<< a = arr f <<< a
 class Arrow a => ArrowZero a where
     zeroArrow :: a b c
 
+-- | @since 2.01
 instance MonadPlus m => ArrowZero (Kleisli m) where
     zeroArrow = Kleisli (\_ -> mzero)
 
@@ -188,6 +192,7 @@ class ArrowZero a => ArrowPlus a where
     -- | An associative operation with identity 'zeroArrow'.
     (<+>) :: a b c -> a b c -> a b c
 
+-- | @since 2.01
 instance MonadPlus m => ArrowPlus (Kleisli m) where
     Kleisli f <+> Kleisli g = Kleisli (\x -> f x `mplus` g x)
 
@@ -269,12 +274,14 @@ class Arrow a => ArrowChoice a where
                 right f . right g = right (f . g)
  #-}
 
+-- | @since 2.01
 instance ArrowChoice (->) where
     left f = f +++ id
     right f = id +++ f
     f +++ g = (Left . f) ||| (Right . g)
     (|||) = either
 
+-- | @since 2.01
 instance Monad m => ArrowChoice (Kleisli m) where
     left f = f +++ arr id
     right f = arr id +++ f
@@ -295,9 +302,11 @@ instance Monad m => ArrowChoice (Kleisli m) where
 class Arrow a => ArrowApply a where
     app :: a (a b c, b) c
 
+-- | @since 2.01
 instance ArrowApply (->) where
     app (f,x) = f x
 
+-- | @since 2.01
 instance Monad m => ArrowApply (Kleisli m) where
     app = Kleisli (\(Kleisli f, x) -> f x)
 
@@ -306,21 +315,26 @@ instance Monad m => ArrowApply (Kleisli m) where
 
 newtype ArrowMonad a b = ArrowMonad (a () b)
 
+-- | @since 4.6.0.0
 instance Arrow a => Functor (ArrowMonad a) where
     fmap f (ArrowMonad m) = ArrowMonad $ m >>> arr f
 
+-- | @since 4.6.0.0
 instance Arrow a => Applicative (ArrowMonad a) where
    pure x = ArrowMonad (arr (const x))
    ArrowMonad f <*> ArrowMonad x = ArrowMonad (f &&& x >>> arr (uncurry id))
 
+-- | @since 2.01
 instance ArrowApply a => Monad (ArrowMonad a) where
     ArrowMonad m >>= f = ArrowMonad $
         m >>> arr (\x -> let ArrowMonad h = f x in (h, ())) >>> app
 
+-- | @since 4.6.0.0
 instance ArrowPlus a => Alternative (ArrowMonad a) where
    empty = ArrowMonad zeroArrow
    ArrowMonad x <|> ArrowMonad y = ArrowMonad (x <+> y)
 
+-- | @since 4.6.0.0
 instance (ArrowApply a, ArrowPlus a) => MonadPlus (ArrowMonad a)
 
 -- | Any instance of 'ArrowApply' can be made into an instance of
@@ -361,12 +375,15 @@ leftApp f = arr ((\b -> (arr (\() -> b) >>> f >>> arr Left, ())) |||
 class Arrow a => ArrowLoop a where
     loop :: a (b,d) (c,d) -> a b c
 
+-- | @since 2.01
 instance ArrowLoop (->) where
     loop f b = let (c,d) = f (b,d) in c
 
 -- | Beware that for many monads (those for which the '>>=' operation
 -- is strict) this instance will /not/ satisfy the right-tightening law
 -- required by the 'ArrowLoop' class.
+--
+-- @since 2.01
 instance MonadFix m => ArrowLoop (Kleisli m) where
     loop (Kleisli f) = Kleisli (liftM fst . mfix . f')
       where f' x y = f (x, snd y)