Export `Monoid(..)`/`Foldable(..)`/`Traversable(..)` from Prelude

This finally exposes also the methods of these 3 classes in the Prelude
in order to allow to define basic class instances w/o needing imports.

This almost completes the primary goal of #9586

NOTE: `fold`, `foldl'`, `foldr'`, and `toList` are not exposed yet,
      as they require upstream fixes for at least `containers` and
      `bytestring`, and are not required for defining basic instances.

Reviewed By: ekmett, austin

Differential Revision: https://phabricator.haskell.org/D236

4 files changed, 12 insertions, 4 deletions

diff --git a/testsuite/tests/ghci/scripts/T4175.stdout b/testsuite/tests/ghci/scripts/T4175.stdout
index e439528965..7c063a6481 100644
--- a/testsuite/tests/ghci/scripts/T4175.stdout
+++ b/testsuite/tests/ghci/scripts/T4175.stdout
@@ -25,6 +25,7 @@ instance Eq () -- Defined in ‘GHC.Classes’
 instance Ord () -- Defined in ‘GHC.Classes’
 instance Read () -- Defined in ‘GHC.Read’
 instance Show () -- Defined in ‘GHC.Show’
+instance Monoid () -- Defined in ‘GHC.Base’
 type instance D () () = Bool 	-- Defined at T4175.hs:22:5
 type instance D Int () = String 	-- Defined at T4175.hs:19:5
 data instance B () = MkB 	-- Defined at T4175.hs:13:15
@@ -38,6 +39,7 @@ instance Show a => Show (Maybe a) -- Defined in ‘GHC.Show’
 instance Applicative Maybe -- Defined in ‘GHC.Base’
 instance Foldable Maybe -- Defined in ‘Data.Foldable’
 instance Traversable Maybe -- Defined in ‘Data.Traversable’
+instance Monoid a => Monoid (Maybe a) -- Defined in ‘GHC.Base’
 type instance A (Maybe a) a = a 	-- Defined at T4175.hs:9:1
 data Int = I# Int# 	-- Defined in ‘GHC.Types’
 instance C Int -- Defined at T4175.hs:18:10
diff --git a/testsuite/tests/ghci/scripts/T7627.stdout b/testsuite/tests/ghci/scripts/T7627.stdout
index 451c7051df..27135662d4 100644
--- a/testsuite/tests/ghci/scripts/T7627.stdout
+++ b/testsuite/tests/ghci/scripts/T7627.stdout
@@ -5,6 +5,7 @@ instance Eq () -- Defined in ‘GHC.Classes’
 instance Ord () -- Defined in ‘GHC.Classes’
 instance Read () -- Defined in ‘GHC.Read’
 instance Show () -- Defined in ‘GHC.Show’
+instance Monoid () -- Defined in ‘GHC.Base’
 data (##) = (##) 	-- Defined in ‘GHC.Prim’
 () :: ()
 (##) :: (# #)
@@ -18,10 +19,11 @@ instance Functor ((,) a) -- Defined in ‘GHC.Base’
 instance (Ord a, Ord b) => Ord (a, b) -- Defined in ‘GHC.Classes’
 instance (Read a, Read b) => Read (a, b) -- Defined in ‘GHC.Read’
 instance (Show a, Show b) => Show (a, b) -- Defined in ‘GHC.Show’
-instance GHC.Base.Monoid a => Applicative ((,) a)
-  -- Defined in ‘GHC.Base’
+instance Monoid a => Applicative ((,) a) -- Defined in ‘GHC.Base’
 instance Foldable ((,) a) -- Defined in ‘Data.Foldable’
 instance Traversable ((,) a) -- Defined in ‘Data.Traversable’
+instance (Monoid a, Monoid b) => Monoid (a, b)
+  -- Defined in ‘GHC.Base’
 data (#,#) (a :: OpenKind) (b :: OpenKind) = (#,#) a b
   	-- Defined in ‘GHC.Prim’
 (,) :: a -> b -> (a, b)
diff --git a/testsuite/tests/ghci/scripts/ghci011.stdout b/testsuite/tests/ghci/scripts/ghci011.stdout
index 0563b83e66..a608f079b5 100644
--- a/testsuite/tests/ghci/scripts/ghci011.stdout
+++ b/testsuite/tests/ghci/scripts/ghci011.stdout
@@ -8,6 +8,7 @@ instance Show a => Show [a] -- Defined in ‘GHC.Show’
 instance Applicative [] -- Defined in ‘GHC.Base’
 instance Foldable [] -- Defined in ‘Data.Foldable’
 instance Traversable [] -- Defined in ‘Data.Traversable’
+instance Monoid [a] -- Defined in ‘GHC.Base’
 data () = () 	-- Defined in ‘GHC.Tuple’
 instance Bounded () -- Defined in ‘GHC.Enum’
 instance Enum () -- Defined in ‘GHC.Enum’
@@ -15,6 +16,7 @@ instance Eq () -- Defined in ‘GHC.Classes’
 instance Ord () -- Defined in ‘GHC.Classes’
 instance Read () -- Defined in ‘GHC.Read’
 instance Show () -- Defined in ‘GHC.Show’
+instance Monoid () -- Defined in ‘GHC.Base’
 data (,) a b = (,) a b 	-- Defined in ‘GHC.Tuple’
 instance (Bounded a, Bounded b) => Bounded (a, b)
   -- Defined in ‘GHC.Enum’
@@ -23,7 +25,8 @@ instance Functor ((,) a) -- Defined in ‘GHC.Base’
 instance (Ord a, Ord b) => Ord (a, b) -- Defined in ‘GHC.Classes’
 instance (Read a, Read b) => Read (a, b) -- Defined in ‘GHC.Read’
 instance (Show a, Show b) => Show (a, b) -- Defined in ‘GHC.Show’
-instance GHC.Base.Monoid a => Applicative ((,) a)
-  -- Defined in ‘GHC.Base’
+instance Monoid a => Applicative ((,) a) -- Defined in ‘GHC.Base’
 instance Foldable ((,) a) -- Defined in ‘Data.Foldable’
 instance Traversable ((,) a) -- Defined in ‘Data.Traversable’
+instance (Monoid a, Monoid b) => Monoid (a, b)
+  -- Defined in ‘GHC.Base’
diff --git a/testsuite/tests/ghci/scripts/ghci020.stdout b/testsuite/tests/ghci/scripts/ghci020.stdout
index bd3a045871..749a244f1f 100644
--- a/testsuite/tests/ghci/scripts/ghci020.stdout
+++ b/testsuite/tests/ghci/scripts/ghci020.stdout
@@ -2,3 +2,4 @@ data (->) a b 	-- Defined in ‘GHC.Prim’
 instance Monad ((->) r) -- Defined in ‘GHC.Base’
 instance Functor ((->) r) -- Defined in ‘GHC.Base’
 instance Applicative ((->) a) -- Defined in ‘GHC.Base’
+instance Monoid b => Monoid (a -> b) -- Defined in ‘GHC.Base’