Minor documentation fixes (#927)

* Add `@since` annotations for the `MonadZip` instances for
  `Data.Sequence` and `Data.Tree`.

* Fix Haddock markup.

Author: treeowl

containers/src/Data/Sequence/Internal.hs

@@ -4659,6 +4659,8 @@ splitMapNode splt f s (Node3 ns a b c) = Node3 ns (f first a) (f second b) (f th
 -- | @ 'mzipWith' = 'zipWith' @
 --
 -- @ 'munzip' = 'unzip' @
+--
+-- @since 0.5.10.1
 instance MonadZip Seq where
   mzipWith = zipWith
   munzip = unzip

containers/src/Data/Tree.hs

@@ -302,6 +302,7 @@ foldlMap1 f g =  -- Use a lambda to allow inlining with two arguments
 instance NFData a => NFData (Tree a) where
     rnf (Node x ts) = rnf x `seq` rnf ts
 
+-- | @since 0.5.10.1
 instance MonadZip Tree where
   mzipWith f (Node a as) (Node b bs)
     = Node (f a b) (mzipWith (mzipWith f) as bs)
@@ -489,8 +490,9 @@ unfoldForestM f = Prelude.mapM (unfoldTreeM f)
 --
 -- See 'unfoldTree' for more info.
 --
--- Implemented using an algorithm adapted from /Breadth-First Numbering: Lessons
--- from a Small Exercise in Algorithm Design/, by Chris Okasaki, /ICFP'00/.
+-- Implemented using an algorithm adapted from
+-- /Breadth-First Numbering: Lessons from a Small Exercise in Algorithm Design/,
+-- by Chris Okasaki, /ICFP'00/.
 unfoldTreeM_BF :: Monad m => (b -> m (a, [b])) -> b -> m (Tree a)
 unfoldTreeM_BF f b = liftM getElement $ unfoldForestQ f (singleton b)
   where
@@ -502,8 +504,9 @@ unfoldTreeM_BF f b = liftM getElement $ unfoldForestQ f (singleton b)
 --
 -- See 'unfoldForest' for more info.
 --
--- Implemented using an algorithm adapted from /Breadth-First Numbering: Lessons
--- from a Small Exercise in Algorithm Design/, by Chris Okasaki, /ICFP'00/.
+-- Implemented using an algorithm adapted from
+-- /Breadth-First Numbering: Lessons from a Small Exercise in Algorithm Design/,
+-- by Chris Okasaki, /ICFP'00/.
 unfoldForestM_BF :: Monad m => (b -> m (a, [b])) -> [b] -> m ([Tree a])
 unfoldForestM_BF f = liftM toList . unfoldForestQ f . fromList