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, 16 insertions, 0 deletions

diff --git a/libraries/base/Control/Monad/Fix.hs b/libraries/base/Control/Monad/Fix.hs
index 4862770f26..c8a9ddab58 100644
--- a/libraries/base/Control/Monad/Fix.hs
+++ b/libraries/base/Control/Monad/Fix.hs
@@ -62,60 +62,76 @@ class (Monad m) => MonadFix m where
 
 -- Instances of MonadFix for Prelude monads
 
+-- | @since 2.01
 instance MonadFix Maybe where
     mfix f = let a = f (unJust a) in a
              where unJust (Just x) = x
                    unJust Nothing  = errorWithoutStackTrace "mfix Maybe: Nothing"
 
+-- | @since 2.01
 instance MonadFix [] where
     mfix f = case fix (f . head) of
                []    -> []
                (x:_) -> x : mfix (tail . f)
 
+-- | @since 2.01
 instance MonadFix IO where
     mfix = fixIO
 
+-- | @since 2.01
 instance MonadFix ((->) r) where
     mfix f = \ r -> let a = f a r in a
 
+-- | @since 4.3.0.0
 instance MonadFix (Either e) where
     mfix f = let a = f (unRight a) in a
              where unRight (Right x) = x
                    unRight (Left  _) = errorWithoutStackTrace "mfix Either: Left"
 
+-- | @since 2.01
 instance MonadFix (ST s) where
         mfix = fixST
 
 -- Instances of Data.Monoid wrappers
 
+-- | @since 4.8.0.0
 instance MonadFix Dual where
     mfix f   = Dual (fix (getDual . f))
 
+-- | @since 4.8.0.0
 instance MonadFix Sum where
     mfix f   = Sum (fix (getSum . f))
 
+-- | @since 4.8.0.0
 instance MonadFix Product where
     mfix f   = Product (fix (getProduct . f))
 
+-- | @since 4.8.0.0
 instance MonadFix First where
     mfix f   = First (mfix (getFirst . f))
 
+-- | @since 4.8.0.0
 instance MonadFix Last where
     mfix f   = Last (mfix (getLast . f))
 
+-- | @since 4.8.0.0
 instance MonadFix f => MonadFix (Alt f) where
     mfix f   = Alt (mfix (getAlt . f))
 
 -- Instances for GHC.Generics
+-- | @since 4.9.0.0
 instance MonadFix Par1 where
     mfix f = Par1 (fix (unPar1 . f))
 
+-- | @since 4.9.0.0
 instance MonadFix f => MonadFix (Rec1 f) where
     mfix f = Rec1 (mfix (unRec1 . f))
 
+-- | @since 4.9.0.0
 instance MonadFix f => MonadFix (M1 i c f) where
     mfix f = M1 (mfix (unM1. f))
 
+-- | @since 4.9.0.0
 instance (MonadFix f, MonadFix g) => MonadFix (f :*: g) where
     mfix f = (mfix (fstP . f)) :*: (mfix (sndP . f))
       where