From 5595ce07a7548fbc9c8367106a4cd6bcbba5a55c Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Tue, 22 Aug 2017 12:42:51 -0400
Subject: [PATCH 01/57] Copy in the Data.Functor.Classes.Pretty module.

---
 prettyprinter/prettyprinter.cabal             |  2 +
 .../src/Data/Functor/Classes/Pretty.hs        | 62 +++++++++++++++++++
 2 files changed, 64 insertions(+)
 create mode 100644 prettyprinter/src/Data/Functor/Classes/Pretty.hs

diff --git a/prettyprinter/prettyprinter.cabal b/prettyprinter/prettyprinter.cabal
index fee98d0c..b851dd94 100644
--- a/prettyprinter/prettyprinter.cabal
+++ b/prettyprinter/prettyprinter.cabal
@@ -40,6 +40,8 @@ library
         , Data.Text.Prettyprint.Doc.Symbols.Unicode
         , Data.Text.Prettyprint.Doc.Symbols.Ascii
 
+        , Data.Functor.Classes.Pretty
+
         -- Deprecated
         , Data.Text.Prettyprint.Doc.Render.ShowS
 
diff --git a/prettyprinter/src/Data/Functor/Classes/Pretty.hs b/prettyprinter/src/Data/Functor/Classes/Pretty.hs
new file mode 100644
index 00000000..9062ea98
--- /dev/null
+++ b/prettyprinter/src/Data/Functor/Classes/Pretty.hs
@@ -0,0 +1,62 @@
+module Data.Functor.Classes.Pretty
+( Pretty1(..)
+, Pretty2(..)
+, module Pretty
+, pretty1
+, Pretty1Of(..)
+, Pretty2Of(..)
+) where
+
+import Data.Text.Prettyprint.Doc as Pretty
+
+class Pretty1 f where
+  liftPretty :: (a -> Doc ann) -> ([a] -> Doc ann) -> f a -> Doc ann
+  liftPrettyList :: (a -> Doc ann) -> ([a] -> Doc ann) -> [f a] -> Doc ann
+  liftPrettyList p pl = list . map (liftPretty p pl)
+
+class Pretty2 f where
+  liftPretty2 :: (a -> Doc ann) -> ([a] -> Doc ann) -> (b -> Doc ann) -> ([b] -> Doc ann) -> f a b -> Doc ann
+  liftPrettyList2 :: (a -> Doc ann) -> ([a] -> Doc ann) -> (b -> Doc ann) -> ([b] -> Doc ann) -> [f a b] -> Doc ann
+  liftPrettyList2 pa pla pb plb = list . map (liftPretty2 pa pla pb plb)
+
+pretty1 :: (Pretty a, Pretty1 f) => f a -> Doc ann
+pretty1 = liftPretty pretty prettyList
+
+instance Pretty1 [] where
+  liftPretty _ pl = pl
+
+instance Pretty2 Either where
+  liftPretty2 pL _ _ _ (Left l)  = pL l
+  liftPretty2 _ _ pR _ (Right r) = pR r
+
+instance Pretty l => Pretty1 (Either l) where
+  liftPretty = liftPretty2 pretty prettyList
+
+instance Pretty2 (,) where
+  liftPretty2 pA _ pB _ (a, b) = tupled [ pA a, pB b ]
+
+instance Pretty a => Pretty1 ((,) a) where
+  liftPretty = liftPretty2 pretty prettyList
+
+
+newtype Pretty1Of f a = Pretty1Of { unPretty1Of :: f a }
+  deriving (Eq, Ord, Show)
+
+instance Pretty1 f => Pretty1 (Pretty1Of f) where
+  liftPretty p pl = liftPretty p pl . unPretty1Of
+
+instance (Pretty1 f, Pretty a) => Pretty (Pretty1Of f a) where
+  pretty = pretty1
+
+
+newtype Pretty2Of f a b = Pretty2Of { unPretty2Of :: f a b }
+  deriving (Eq, Ord, Show)
+
+instance Pretty2 f => Pretty2 (Pretty2Of f) where
+  liftPretty2 pA plA pB plB = liftPretty2 pA plA pB plB . unPretty2Of
+
+instance (Pretty2 f, Pretty a) => Pretty1 (Pretty2Of f a) where
+  liftPretty = liftPretty2 pretty prettyList
+
+instance (Pretty2 f, Pretty a, Pretty b) => Pretty (Pretty2Of f a b) where
+  pretty = pretty1

From d3a44cffb796c21963484b435a2589bde4b41037 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Tue, 22 Aug 2017 13:31:58 -0400
Subject: [PATCH 02/57] Define generically-derivable Pretty1 instances.

---
 .../src/Data/Functor/Classes/Pretty.hs        | 42 +++++++++++++++++++
 1 file changed, 42 insertions(+)

diff --git a/prettyprinter/src/Data/Functor/Classes/Pretty.hs b/prettyprinter/src/Data/Functor/Classes/Pretty.hs
index 9062ea98..f3f9d25a 100644
--- a/prettyprinter/src/Data/Functor/Classes/Pretty.hs
+++ b/prettyprinter/src/Data/Functor/Classes/Pretty.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE FlexibleInstances, TypeOperators #-}
 module Data.Functor.Classes.Pretty
 ( Pretty1(..)
 , Pretty2(..)
@@ -8,6 +9,7 @@ module Data.Functor.Classes.Pretty
 ) where
 
 import Data.Text.Prettyprint.Doc as Pretty
+import GHC.Generics
 
 class Pretty1 f where
   liftPretty :: (a -> Doc ann) -> ([a] -> Doc ann) -> f a -> Doc ann
@@ -60,3 +62,43 @@ instance (Pretty2 f, Pretty a) => Pretty1 (Pretty2Of f a) where
 
 instance (Pretty2 f, Pretty a, Pretty b) => Pretty (Pretty2Of f a b) where
   pretty = pretty1
+
+
+-- Generics
+
+class GPretty1 f where
+  gliftPretty :: (a -> Doc ann) -> ([a] -> Doc ann) -> f a -> Doc ann
+  gcollectPretty :: (a -> Doc ann) -> ([a] -> Doc ann) -> f a -> [Doc ann]
+  gcollectPretty p pl a = [gliftPretty p pl a]
+
+instance GPretty1 U1 where
+  gliftPretty _ _ _ = emptyDoc
+
+instance GPretty1 Par1 where
+  gliftPretty p _ (Par1 a) = p a
+
+instance Pretty c => GPretty1 (K1 i c) where
+  gliftPretty _ _ (K1 a) = pretty a
+
+instance Pretty1 f => GPretty1 (Rec1 f) where
+  gliftPretty p pl (Rec1 a) = liftPretty p pl a
+
+instance GPretty1 f => GPretty1 (M1 D c f) where
+  gliftPretty p pl (M1 a) = gliftPretty p pl a
+
+instance (Constructor c, GPretty1 f) => GPretty1 (M1 C c f) where
+  gliftPretty p pl m = nest 2 (vsep (pretty (conName m) : gcollectPretty p pl (unM1 m)))
+
+instance GPretty1 f => GPretty1 (M1 S c f) where
+  gliftPretty p pl (M1 a) = gliftPretty p pl a
+
+instance (GPretty1 f, GPretty1 g) => GPretty1 (f :+: g) where
+  gliftPretty p pl (L1 l) = gliftPretty p pl l
+  gliftPretty p pl (R1 r) = gliftPretty p pl r
+
+instance (GPretty1 f, GPretty1 g) => GPretty1 (f :*: g) where
+  gliftPretty p pl (a :*: b) = gliftPretty p pl a <+> gliftPretty p pl b
+  gcollectPretty p pl (a :*: b) = gcollectPretty p pl a <> gcollectPretty p pl b
+
+instance (Pretty1 f, GPretty1 g) => GPretty1 (f :.: g) where
+  gliftPretty p pl (Comp1 a) = liftPretty (gliftPretty p pl) (list . map (gliftPretty p pl)) a

From 00f7bb3e7fe28dd56c663e565d464ffcea4361da Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Tue, 22 Aug 2017 13:35:09 -0400
Subject: [PATCH 03/57] Give a default implementation of liftPretty for
 Generic1 types.

---
 prettyprinter/src/Data/Functor/Classes/Pretty.hs | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/prettyprinter/src/Data/Functor/Classes/Pretty.hs b/prettyprinter/src/Data/Functor/Classes/Pretty.hs
index f3f9d25a..0496e9d9 100644
--- a/prettyprinter/src/Data/Functor/Classes/Pretty.hs
+++ b/prettyprinter/src/Data/Functor/Classes/Pretty.hs
@@ -1,4 +1,4 @@
-{-# LANGUAGE FlexibleInstances, TypeOperators #-}
+{-# LANGUAGE DefaultSignatures, FlexibleContexts, FlexibleInstances, TypeOperators #-}
 module Data.Functor.Classes.Pretty
 ( Pretty1(..)
 , Pretty2(..)
@@ -13,6 +13,9 @@ import GHC.Generics
 
 class Pretty1 f where
   liftPretty :: (a -> Doc ann) -> ([a] -> Doc ann) -> f a -> Doc ann
+  default liftPretty :: (Generic1 f, GPretty1 (Rep1 f)) => (a -> Doc ann) -> ([a] -> Doc ann) -> f a -> Doc ann
+  liftPretty p pl = gliftPretty p pl . from1
+
   liftPrettyList :: (a -> Doc ann) -> ([a] -> Doc ann) -> [f a] -> Doc ann
   liftPrettyList p pl = list . map (liftPretty p pl)
 

From c51c52bb02b21102c16b90a5669dfeb00706aaa2 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Tue, 22 Aug 2017 13:53:27 -0400
Subject: [PATCH 04/57] Define a Pretty1 instance for NonEmpty.

---
 prettyprinter/src/Data/Functor/Classes/Pretty.hs | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/prettyprinter/src/Data/Functor/Classes/Pretty.hs b/prettyprinter/src/Data/Functor/Classes/Pretty.hs
index 0496e9d9..dd3aefe2 100644
--- a/prettyprinter/src/Data/Functor/Classes/Pretty.hs
+++ b/prettyprinter/src/Data/Functor/Classes/Pretty.hs
@@ -8,6 +8,8 @@ module Data.Functor.Classes.Pretty
 , Pretty2Of(..)
 ) where
 
+import Data.Foldable (toList)
+import Data.List.NonEmpty (NonEmpty(..))
 import Data.Text.Prettyprint.Doc as Pretty
 import GHC.Generics
 
@@ -30,6 +32,9 @@ pretty1 = liftPretty pretty prettyList
 instance Pretty1 [] where
   liftPretty _ pl = pl
 
+instance Pretty1 NonEmpty where
+  liftPretty _ pl = pl . toList
+
 instance Pretty2 Either where
   liftPretty2 pL _ _ _ (Left l)  = pL l
   liftPretty2 _ _ pR _ (Right r) = pR r

From 80823254bbed62f2b145b1ae814bdcf6fd38cccb Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Tue, 22 Aug 2017 13:54:19 -0400
Subject: [PATCH 05/57] Define a Pretty1 instance for Maybe.

---
 prettyprinter/src/Data/Functor/Classes/Pretty.hs | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/prettyprinter/src/Data/Functor/Classes/Pretty.hs b/prettyprinter/src/Data/Functor/Classes/Pretty.hs
index dd3aefe2..7b233b8e 100644
--- a/prettyprinter/src/Data/Functor/Classes/Pretty.hs
+++ b/prettyprinter/src/Data/Functor/Classes/Pretty.hs
@@ -35,6 +35,9 @@ instance Pretty1 [] where
 instance Pretty1 NonEmpty where
   liftPretty _ pl = pl . toList
 
+instance Pretty1 Maybe where
+  liftPretty p _ = maybe emptyDoc p
+
 instance Pretty2 Either where
   liftPretty2 pL _ _ _ (Left l)  = pL l
   liftPretty2 _ _ pR _ (Right r) = pR r

From 2247b13c574b1dc820315aefe456f142b5372319 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 23 Aug 2017 09:48:26 -0400
Subject: [PATCH 06/57] :fire: Pretty1Of & Pretty2Of.

---
 .../src/Data/Functor/Classes/Pretty.hs        | 23 -------------------
 1 file changed, 23 deletions(-)

diff --git a/prettyprinter/src/Data/Functor/Classes/Pretty.hs b/prettyprinter/src/Data/Functor/Classes/Pretty.hs
index 7b233b8e..c0db370c 100644
--- a/prettyprinter/src/Data/Functor/Classes/Pretty.hs
+++ b/prettyprinter/src/Data/Functor/Classes/Pretty.hs
@@ -52,29 +52,6 @@ instance Pretty a => Pretty1 ((,) a) where
   liftPretty = liftPretty2 pretty prettyList
 
 
-newtype Pretty1Of f a = Pretty1Of { unPretty1Of :: f a }
-  deriving (Eq, Ord, Show)
-
-instance Pretty1 f => Pretty1 (Pretty1Of f) where
-  liftPretty p pl = liftPretty p pl . unPretty1Of
-
-instance (Pretty1 f, Pretty a) => Pretty (Pretty1Of f a) where
-  pretty = pretty1
-
-
-newtype Pretty2Of f a b = Pretty2Of { unPretty2Of :: f a b }
-  deriving (Eq, Ord, Show)
-
-instance Pretty2 f => Pretty2 (Pretty2Of f) where
-  liftPretty2 pA plA pB plB = liftPretty2 pA plA pB plB . unPretty2Of
-
-instance (Pretty2 f, Pretty a) => Pretty1 (Pretty2Of f a) where
-  liftPretty = liftPretty2 pretty prettyList
-
-instance (Pretty2 f, Pretty a, Pretty b) => Pretty (Pretty2Of f a b) where
-  pretty = pretty1
-
-
 -- Generics
 
 class GPretty1 f where

From 96e21f9e99699311860f2c3826b055dec54371f9 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 23 Aug 2017 09:57:21 -0400
Subject: [PATCH 07/57] Define Pretty1 & Pretty2 in
 Data.Text.PrettyPrint.Doc.Internal.

---
 .../src/Data/Text/Prettyprint/Doc/Internal.hs        | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index 68318f78..665a6c33 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -353,6 +353,18 @@ instance Pretty Lazy.Text where pretty = pretty . Lazy.toStrict
 instance Pretty Void where pretty = absurd
 
 
+class Pretty1 f where
+    liftPretty :: (a -> Doc ann) -> ([a] -> Doc ann) -> f a -> Doc ann
+
+    liftPrettyList :: (a -> Doc ann) -> ([a] -> Doc ann) -> [f a] -> Doc ann
+    liftPrettyList p pl = list . map (liftPretty p pl)
+
+class Pretty2 f where
+    liftPretty2 :: (a -> Doc ann) -> ([a] -> Doc ann) -> (b -> Doc ann) -> ([b] -> Doc ann) -> f a b -> Doc ann
+
+    liftPrettyList2 :: (a -> Doc ann) -> ([a] -> Doc ann) -> (b -> Doc ann) -> ([b] -> Doc ann) -> [f a b] -> Doc ann
+    liftPrettyList2 pa pla pb plb = list . map (liftPretty2 pa pla pb plb)
+
 
 -- | @(unsafeTextWithoutNewlines s)@ contains the literal string @s@.
 --

From 680d6e24b27ea2904a678230ffc1c09503c5f909 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 23 Aug 2017 09:57:33 -0400
Subject: [PATCH 08/57] :memo: Pretty1 & Pretty2.

---
 .../src/Data/Text/Prettyprint/Doc/Internal.hs          | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index 665a6c33..9aa165d6 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -353,12 +353,22 @@ instance Pretty Lazy.Text where pretty = pretty . Lazy.toStrict
 instance Pretty Void where pretty = absurd
 
 
+-- | Overloaded conversion to 'Doc', lifted to unary type constructors.
+--
+-- Laws:
+--
+--   1. output should be pretty. :-)
 class Pretty1 f where
     liftPretty :: (a -> Doc ann) -> ([a] -> Doc ann) -> f a -> Doc ann
 
     liftPrettyList :: (a -> Doc ann) -> ([a] -> Doc ann) -> [f a] -> Doc ann
     liftPrettyList p pl = list . map (liftPretty p pl)
 
+-- | Overloaded conversion to 'Doc', lifted to binary type constructors.
+--
+-- Laws:
+--
+--   1. output should be pretty. :-)
 class Pretty2 f where
     liftPretty2 :: (a -> Doc ann) -> ([a] -> Doc ann) -> (b -> Doc ann) -> ([b] -> Doc ann) -> f a b -> Doc ann
 

From f8e3343ce46a1c454ae59267e9cc003b43b5bb5b Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 23 Aug 2017 10:02:04 -0400
Subject: [PATCH 09/57] :fire: liftPrettyList/liftPrettyList2.

---
 prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index 9aa165d6..2504311f 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -361,9 +361,6 @@ instance Pretty Void where pretty = absurd
 class Pretty1 f where
     liftPretty :: (a -> Doc ann) -> ([a] -> Doc ann) -> f a -> Doc ann
 
-    liftPrettyList :: (a -> Doc ann) -> ([a] -> Doc ann) -> [f a] -> Doc ann
-    liftPrettyList p pl = list . map (liftPretty p pl)
-
 -- | Overloaded conversion to 'Doc', lifted to binary type constructors.
 --
 -- Laws:
@@ -372,9 +369,6 @@ class Pretty1 f where
 class Pretty2 f where
     liftPretty2 :: (a -> Doc ann) -> ([a] -> Doc ann) -> (b -> Doc ann) -> ([b] -> Doc ann) -> f a b -> Doc ann
 
-    liftPrettyList2 :: (a -> Doc ann) -> ([a] -> Doc ann) -> (b -> Doc ann) -> ([b] -> Doc ann) -> [f a b] -> Doc ann
-    liftPrettyList2 pa pla pb plb = list . map (liftPretty2 pa pla pb plb)
-
 
 -- | @(unsafeTextWithoutNewlines s)@ contains the literal string @s@.
 --

From 3f65702c39dd7135ad9e9073aec0e47cf9a63ae8 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 23 Aug 2017 10:02:10 -0400
Subject: [PATCH 10/57] :fire: redundant spacing.

---
 prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs | 2 --
 1 file changed, 2 deletions(-)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index 2504311f..0e528602 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -352,7 +352,6 @@ instance Pretty Lazy.Text where pretty = pretty . Lazy.toStrict
 -- []
 instance Pretty Void where pretty = absurd
 
-
 -- | Overloaded conversion to 'Doc', lifted to unary type constructors.
 --
 -- Laws:
@@ -369,7 +368,6 @@ class Pretty1 f where
 class Pretty2 f where
     liftPretty2 :: (a -> Doc ann) -> ([a] -> Doc ann) -> (b -> Doc ann) -> ([b] -> Doc ann) -> f a b -> Doc ann
 
-
 -- | @(unsafeTextWithoutNewlines s)@ contains the literal string @s@.
 --
 -- The string must not contain any newline characters, since this is an

From 73dd98cde3c2d3f787cc0957160172fe58da71ae Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 23 Aug 2017 10:04:16 -0400
Subject: [PATCH 11/57] Reformat liftPretty/liftPretty2.

---
 .../src/Data/Text/Prettyprint/Doc/Internal.hs        | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index 0e528602..4a94aebd 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -358,7 +358,10 @@ instance Pretty Void where pretty = absurd
 --
 --   1. output should be pretty. :-)
 class Pretty1 f where
-    liftPretty :: (a -> Doc ann) -> ([a] -> Doc ann) -> f a -> Doc ann
+    liftPretty :: (a -> Doc ann)
+               -> ([a] -> Doc ann)
+               -> f a
+               -> Doc ann
 
 -- | Overloaded conversion to 'Doc', lifted to binary type constructors.
 --
@@ -366,7 +369,12 @@ class Pretty1 f where
 --
 --   1. output should be pretty. :-)
 class Pretty2 f where
-    liftPretty2 :: (a -> Doc ann) -> ([a] -> Doc ann) -> (b -> Doc ann) -> ([b] -> Doc ann) -> f a b -> Doc ann
+    liftPretty2 :: (a -> Doc ann)
+                -> ([a] -> Doc ann)
+                -> (b -> Doc ann)
+                -> ([b] -> Doc ann)
+                -> f a b
+                -> Doc ann
 
 -- | @(unsafeTextWithoutNewlines s)@ contains the literal string @s@.
 --

From 6d8d0af4058cd55e6fbae06222b6910969407197 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 23 Aug 2017 10:05:23 -0400
Subject: [PATCH 12/57] Add newlines after class declarations.

---
 prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index 4a94aebd..bdf37f13 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -358,6 +358,7 @@ instance Pretty Void where pretty = absurd
 --
 --   1. output should be pretty. :-)
 class Pretty1 f where
+
     liftPretty :: (a -> Doc ann)
                -> ([a] -> Doc ann)
                -> f a
@@ -369,6 +370,7 @@ class Pretty1 f where
 --
 --   1. output should be pretty. :-)
 class Pretty2 f where
+
     liftPretty2 :: (a -> Doc ann)
                 -> ([a] -> Doc ann)
                 -> (b -> Doc ann)

From 7cafb338dd03c6def060bb1edd46b58b93385f86 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 23 Aug 2017 10:07:55 -0400
Subject: [PATCH 13/57] :memo: liftPretty.

---
 prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index bdf37f13..8abc4ac3 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -359,6 +359,8 @@ instance Pretty Void where pretty = absurd
 --   1. output should be pretty. :-)
 class Pretty1 f where
 
+    -- | >>> liftPretty (\ s -> pretty s <> dot) (Just "hello")
+    -- hello.
     liftPretty :: (a -> Doc ann)
                -> ([a] -> Doc ann)
                -> f a

From 9579404348820810aa9a222dd1924b9d9425cd59 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 23 Aug 2017 10:08:54 -0400
Subject: [PATCH 14/57] :fire: Data.Functor.Classes.Pretty.

---
 prettyprinter/prettyprinter.cabal             |  2 -
 .../src/Data/Functor/Classes/Pretty.hs        | 92 -------------------
 2 files changed, 94 deletions(-)
 delete mode 100644 prettyprinter/src/Data/Functor/Classes/Pretty.hs

diff --git a/prettyprinter/prettyprinter.cabal b/prettyprinter/prettyprinter.cabal
index b851dd94..fee98d0c 100644
--- a/prettyprinter/prettyprinter.cabal
+++ b/prettyprinter/prettyprinter.cabal
@@ -40,8 +40,6 @@ library
         , Data.Text.Prettyprint.Doc.Symbols.Unicode
         , Data.Text.Prettyprint.Doc.Symbols.Ascii
 
-        , Data.Functor.Classes.Pretty
-
         -- Deprecated
         , Data.Text.Prettyprint.Doc.Render.ShowS
 
diff --git a/prettyprinter/src/Data/Functor/Classes/Pretty.hs b/prettyprinter/src/Data/Functor/Classes/Pretty.hs
deleted file mode 100644
index c0db370c..00000000
--- a/prettyprinter/src/Data/Functor/Classes/Pretty.hs
+++ /dev/null
@@ -1,92 +0,0 @@
-{-# LANGUAGE DefaultSignatures, FlexibleContexts, FlexibleInstances, TypeOperators #-}
-module Data.Functor.Classes.Pretty
-( Pretty1(..)
-, Pretty2(..)
-, module Pretty
-, pretty1
-, Pretty1Of(..)
-, Pretty2Of(..)
-) where
-
-import Data.Foldable (toList)
-import Data.List.NonEmpty (NonEmpty(..))
-import Data.Text.Prettyprint.Doc as Pretty
-import GHC.Generics
-
-class Pretty1 f where
-  liftPretty :: (a -> Doc ann) -> ([a] -> Doc ann) -> f a -> Doc ann
-  default liftPretty :: (Generic1 f, GPretty1 (Rep1 f)) => (a -> Doc ann) -> ([a] -> Doc ann) -> f a -> Doc ann
-  liftPretty p pl = gliftPretty p pl . from1
-
-  liftPrettyList :: (a -> Doc ann) -> ([a] -> Doc ann) -> [f a] -> Doc ann
-  liftPrettyList p pl = list . map (liftPretty p pl)
-
-class Pretty2 f where
-  liftPretty2 :: (a -> Doc ann) -> ([a] -> Doc ann) -> (b -> Doc ann) -> ([b] -> Doc ann) -> f a b -> Doc ann
-  liftPrettyList2 :: (a -> Doc ann) -> ([a] -> Doc ann) -> (b -> Doc ann) -> ([b] -> Doc ann) -> [f a b] -> Doc ann
-  liftPrettyList2 pa pla pb plb = list . map (liftPretty2 pa pla pb plb)
-
-pretty1 :: (Pretty a, Pretty1 f) => f a -> Doc ann
-pretty1 = liftPretty pretty prettyList
-
-instance Pretty1 [] where
-  liftPretty _ pl = pl
-
-instance Pretty1 NonEmpty where
-  liftPretty _ pl = pl . toList
-
-instance Pretty1 Maybe where
-  liftPretty p _ = maybe emptyDoc p
-
-instance Pretty2 Either where
-  liftPretty2 pL _ _ _ (Left l)  = pL l
-  liftPretty2 _ _ pR _ (Right r) = pR r
-
-instance Pretty l => Pretty1 (Either l) where
-  liftPretty = liftPretty2 pretty prettyList
-
-instance Pretty2 (,) where
-  liftPretty2 pA _ pB _ (a, b) = tupled [ pA a, pB b ]
-
-instance Pretty a => Pretty1 ((,) a) where
-  liftPretty = liftPretty2 pretty prettyList
-
-
--- Generics
-
-class GPretty1 f where
-  gliftPretty :: (a -> Doc ann) -> ([a] -> Doc ann) -> f a -> Doc ann
-  gcollectPretty :: (a -> Doc ann) -> ([a] -> Doc ann) -> f a -> [Doc ann]
-  gcollectPretty p pl a = [gliftPretty p pl a]
-
-instance GPretty1 U1 where
-  gliftPretty _ _ _ = emptyDoc
-
-instance GPretty1 Par1 where
-  gliftPretty p _ (Par1 a) = p a
-
-instance Pretty c => GPretty1 (K1 i c) where
-  gliftPretty _ _ (K1 a) = pretty a
-
-instance Pretty1 f => GPretty1 (Rec1 f) where
-  gliftPretty p pl (Rec1 a) = liftPretty p pl a
-
-instance GPretty1 f => GPretty1 (M1 D c f) where
-  gliftPretty p pl (M1 a) = gliftPretty p pl a
-
-instance (Constructor c, GPretty1 f) => GPretty1 (M1 C c f) where
-  gliftPretty p pl m = nest 2 (vsep (pretty (conName m) : gcollectPretty p pl (unM1 m)))
-
-instance GPretty1 f => GPretty1 (M1 S c f) where
-  gliftPretty p pl (M1 a) = gliftPretty p pl a
-
-instance (GPretty1 f, GPretty1 g) => GPretty1 (f :+: g) where
-  gliftPretty p pl (L1 l) = gliftPretty p pl l
-  gliftPretty p pl (R1 r) = gliftPretty p pl r
-
-instance (GPretty1 f, GPretty1 g) => GPretty1 (f :*: g) where
-  gliftPretty p pl (a :*: b) = gliftPretty p pl a <+> gliftPretty p pl b
-  gcollectPretty p pl (a :*: b) = gcollectPretty p pl a <> gcollectPretty p pl b
-
-instance (Pretty1 f, GPretty1 g) => GPretty1 (f :.: g) where
-  gliftPretty p pl (Comp1 a) = liftPretty (gliftPretty p pl) (list . map (gliftPretty p pl)) a

From add8798c34d847aadcc1869ff93fd2658e340047 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 23 Aug 2017 10:17:25 -0400
Subject: [PATCH 15/57] Define a bunch of Pretty1 instances.

---
 .../src/Data/Text/Prettyprint/Doc/Internal.hs        | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index 8abc4ac3..e58f8ec4 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -366,6 +366,18 @@ class Pretty1 f where
                -> f a
                -> Doc ann
 
+instance Pretty1 [] where
+    liftPretty _ prettyList' = prettyList'
+
+instance Pretty1 NonEmpty where
+    liftPretty _ prettyList' (x:|xs) = prettyList' (x:xs)
+
+instance Pretty1 Maybe where
+    liftPretty p _ = maybe emptyDoc p
+
+instance Pretty a => Pretty1 ((,) a) where
+    liftPretty pretty2 _ (x1, x2) = tupled [pretty x1, pretty2 x2]
+
 -- | Overloaded conversion to 'Doc', lifted to binary type constructors.
 --
 -- Laws:

From ba7ba5650538a9535375852a6b927a22428b9f96 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 23 Aug 2017 10:17:34 -0400
Subject: [PATCH 16/57] :memo: Pretty1 [].

---
 prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index e58f8ec4..82f6dcab 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -366,6 +366,8 @@ class Pretty1 f where
                -> f a
                -> Doc ann
 
+-- | >>> liftPretty (parens . pretty) [1,2,3]
+-- [(1), (2), (3)]
 instance Pretty1 [] where
     liftPretty _ prettyList' = prettyList'
 

From 146ab167fb702f44ee4f06ee710ac577787fb9fd Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 23 Aug 2017 10:17:42 -0400
Subject: [PATCH 17/57] :memo: Pretty1 Maybe.

---
 prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index 82f6dcab..4cc306db 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -374,6 +374,12 @@ instance Pretty1 [] where
 instance Pretty1 NonEmpty where
     liftPretty _ prettyList' (x:|xs) = prettyList' (x:xs)
 
+-- | Ignore 'Nothing's, print 'Just' contents.
+--
+-- >>> liftPretty (parens . pretty) (Just True)
+-- (True)
+-- >>> braces (liftPretty (parens . pretty) (Nothing :: Maybe Bool))
+-- {}
 instance Pretty1 Maybe where
     liftPretty p _ = maybe emptyDoc p
 

From 12ebec7eb0e9c43acc759d26fb890227d327c4de Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 23 Aug 2017 10:17:52 -0400
Subject: [PATCH 18/57] Better :memo: for liftPretty.

---
 prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index 4cc306db..e85b9ee0 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -359,8 +359,8 @@ instance Pretty Void where pretty = absurd
 --   1. output should be pretty. :-)
 class Pretty1 f where
 
-    -- | >>> liftPretty (\ s -> pretty s <> dot) (Just "hello")
-    -- hello.
+    -- | >>> liftPretty (parens . pretty) (Just "hello")
+    -- (hello)
     liftPretty :: (a -> Doc ann)
                -> ([a] -> Doc ann)
                -> f a

From 8f3c30653c2bf83e22cee645c4a4b6cb90ac882a Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 23 Aug 2017 10:18:39 -0400
Subject: [PATCH 19/57] Define a Pretty2 instance for pairs.

---
 prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index e85b9ee0..61425e1b 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -400,6 +400,10 @@ class Pretty2 f where
                 -> f a b
                 -> Doc ann
 
+
+instance Pretty2 (,) where
+    liftPretty2 pretty1 _ pretty2 _ (x1, x2) = tupled [pretty1 x1, pretty2 x2]
+
 -- | @(unsafeTextWithoutNewlines s)@ contains the literal string @s@.
 --
 -- The string must not contain any newline characters, since this is an

From 223b7af13c0e8f3f2b102f0f34603db8932d8169 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 23 Aug 2017 10:19:31 -0400
Subject: [PATCH 20/57] :memo: Pretty1 ((,) a).

---
 prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index 61425e1b..1ef13300 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -383,6 +383,8 @@ instance Pretty1 NonEmpty where
 instance Pretty1 Maybe where
     liftPretty p _ = maybe emptyDoc p
 
+-- | >>> liftPretty (parens . pretty) (123, "hello")
+-- (123, (hello))
 instance Pretty a => Pretty1 ((,) a) where
     liftPretty pretty2 _ (x1, x2) = tupled [pretty x1, pretty2 x2]
 

From 6280232b84f3b3ee264f5d0ef8ee8dd531e0333c Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 23 Aug 2017 10:23:10 -0400
Subject: [PATCH 21/57] Include the list parameter in the :memo:s.

---
 .../src/Data/Text/Prettyprint/Doc/Internal.hs          | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index 1ef13300..d9809f33 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -359,14 +359,14 @@ instance Pretty Void where pretty = absurd
 --   1. output should be pretty. :-)
 class Pretty1 f where
 
-    -- | >>> liftPretty (parens . pretty) (Just "hello")
+    -- | >>> liftPretty (parens . pretty) (list . map (parens . pretty)) (Just "hello")
     -- (hello)
     liftPretty :: (a -> Doc ann)
                -> ([a] -> Doc ann)
                -> f a
                -> Doc ann
 
--- | >>> liftPretty (parens . pretty) [1,2,3]
+-- | >>> liftPretty (parens . pretty) (list . map (parens . pretty)) [1,2,3]
 -- [(1), (2), (3)]
 instance Pretty1 [] where
     liftPretty _ prettyList' = prettyList'
@@ -376,14 +376,14 @@ instance Pretty1 NonEmpty where
 
 -- | Ignore 'Nothing's, print 'Just' contents.
 --
--- >>> liftPretty (parens . pretty) (Just True)
+-- >>> liftPretty (parens . pretty) (list . map (parens . pretty)) (Just True)
 -- (True)
--- >>> braces (liftPretty (parens . pretty) (Nothing :: Maybe Bool))
+-- >>> braces (liftPretty (parens . pretty) (list . map (parens . pretty)) (Nothing :: Maybe Bool))
 -- {}
 instance Pretty1 Maybe where
     liftPretty p _ = maybe emptyDoc p
 
--- | >>> liftPretty (parens . pretty) (123, "hello")
+-- | >>> liftPretty (parens . pretty) (list . map (parens . pretty)) (123, "hello")
 -- (123, (hello))
 instance Pretty a => Pretty1 ((,) a) where
     liftPretty pretty2 _ (x1, x2) = tupled [pretty x1, pretty2 x2]

From 00612b751511ea11cd040afd1a74058b5b5faa43 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 23 Aug 2017 10:24:30 -0400
Subject: [PATCH 22/57] :memo: liftPretty2.

---
 prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index d9809f33..5d241e69 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -403,6 +403,8 @@ class Pretty2 f where
                 -> Doc ann
 
 
+-- | >>> liftPretty2 (parens . pretty) (list . map (parens . pretty)) (parens . pretty) (list . map (parens . pretty)) (123, "hello")
+-- ((123), (hello))
 instance Pretty2 (,) where
     liftPretty2 pretty1 _ pretty2 _ (x1, x2) = tupled [pretty1 x1, pretty2 x2]
 

From 5acdc82ed50b88eda6b73c6a6ef091f7f04d426c Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 23 Aug 2017 10:25:26 -0400
Subject: [PATCH 23/57] Define a Pretty instance for Either.

---
 prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index 5d241e69..9118e20f 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -328,6 +328,9 @@ instance Pretty a => Pretty (Maybe a) where
     pretty = maybe mempty pretty
     prettyList = prettyList . catMaybes
 
+instance (Pretty a, Pretty b) => Pretty (Either a b) where
+    pretty = either pretty pretty
+
 -- | Automatically converts all newlines to @'line'@.
 --
 -- >>> pretty ("hello\nworld" :: Text)

From df988099bd896a92fee09f950a0236e5975ce038 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 23 Aug 2017 10:26:16 -0400
Subject: [PATCH 24/57] :memo: Pretty (Either a b).

---
 prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index 9118e20f..5f189d9a 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -328,6 +328,12 @@ instance Pretty a => Pretty (Maybe a) where
     pretty = maybe mempty pretty
     prettyList = prettyList . catMaybes
 
+-- | Print 'Left' and 'Right' contents.
+--
+-- >>> pretty (Left True)
+-- True
+-- >>> pretty (Right True)
+-- True
 instance (Pretty a, Pretty b) => Pretty (Either a b) where
     pretty = either pretty pretty
 

From 4c42bd0adff1b16d6b64c2fdcd248cde01f67182 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 23 Aug 2017 10:28:25 -0400
Subject: [PATCH 25/57] Mirror the Pretty instance for Maybe.

---
 prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index 5f189d9a..17a80a28 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -390,7 +390,7 @@ instance Pretty1 NonEmpty where
 -- >>> braces (liftPretty (parens . pretty) (list . map (parens . pretty)) (Nothing :: Maybe Bool))
 -- {}
 instance Pretty1 Maybe where
-    liftPretty p _ = maybe emptyDoc p
+    liftPretty prettyJust _ = maybe mempty prettyJust
 
 -- | >>> liftPretty (parens . pretty) (list . map (parens . pretty)) (123, "hello")
 -- (123, (hello))

From fce219b8be2a581d719011ca02dd238536fd53e2 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 23 Aug 2017 10:31:29 -0400
Subject: [PATCH 26/57] :memo: why Pretty1.

---
 prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index 17a80a28..8b13e8e8 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -363,6 +363,10 @@ instance Pretty Void where pretty = absurd
 
 -- | Overloaded conversion to 'Doc', lifted to unary type constructors.
 --
+-- This is most useful for defining 'Pretty' instances for recursive types, and
+-- for efficiently pretty-printing 'Functor's whose definitions of 'fmap' don’t
+-- fuse.
+--
 -- Laws:
 --
 --   1. output should be pretty. :-)

From 85d57e407048b4de35c265ad361287b66c72b1e4 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 23 Aug 2017 10:31:44 -0400
Subject: [PATCH 27/57] :memo: why Pretty2.

---
 prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index 8b13e8e8..ed372fb6 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -403,6 +403,10 @@ instance Pretty a => Pretty1 ((,) a) where
 
 -- | Overloaded conversion to 'Doc', lifted to binary type constructors.
 --
+-- This is most useful for defining 'Pretty' instances for recursive types, and
+-- for efficiently pretty-printing 'Functor's whose definitions of 'fmap' don’t
+-- fuse.
+--
 -- Laws:
 --
 --   1. output should be pretty. :-)

From 9d2f6a8c4ae6c93dac9482a747fd94e2868c5622 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 23 Aug 2017 10:32:14 -0400
Subject: [PATCH 28/57] Better :memo: for Pretty1 Maybe.

---
 prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index ed372fb6..d2e43520 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -387,7 +387,7 @@ instance Pretty1 [] where
 instance Pretty1 NonEmpty where
     liftPretty _ prettyList' (x:|xs) = prettyList' (x:xs)
 
--- | Ignore 'Nothing's, print 'Just' contents.
+-- | Ignore 'Nothing's, print 'Just' contents with the supplied function.
 --
 -- >>> liftPretty (parens . pretty) (list . map (parens . pretty)) (Just True)
 -- (True)

From 943163ad8defbfef77f4db6e41d8c9261272f996 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 23 Aug 2017 10:33:09 -0400
Subject: [PATCH 29/57] Define Pretty1 & Pretty2 instances for Either.

---
 prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index d2e43520..3b15f8e9 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -396,6 +396,9 @@ instance Pretty1 NonEmpty where
 instance Pretty1 Maybe where
     liftPretty prettyJust _ = maybe mempty prettyJust
 
+instance Pretty a => Pretty1 (Either a) where
+    liftPretty prettyRight _ = either pretty prettyRight
+
 -- | >>> liftPretty (parens . pretty) (list . map (parens . pretty)) (123, "hello")
 -- (123, (hello))
 instance Pretty a => Pretty1 ((,) a) where
@@ -419,6 +422,8 @@ class Pretty2 f where
                 -> f a b
                 -> Doc ann
 
+instance Pretty2 Either where
+    liftPretty2 prettyLeft _ prettyRight _ = either prettyLeft prettyRight
 
 -- | >>> liftPretty2 (parens . pretty) (list . map (parens . pretty)) (parens . pretty) (list . map (parens . pretty)) (123, "hello")
 -- ((123), (hello))

From 03bd95286a19e9d80b0562f57ca8f80da529bf03 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 23 Aug 2017 10:33:15 -0400
Subject: [PATCH 30/57] :memo: Pretty2 Either.

---
 prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index 3b15f8e9..a269f0f9 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -422,6 +422,12 @@ class Pretty2 f where
                 -> f a b
                 -> Doc ann
 
+-- | Print 'Left' and 'Right' contents with the supplied functions.
+--
+-- >>> liftPretty (parens . pretty) (list . map (parens . pretty)) (Left True)
+-- True
+-- >>> liftPretty (parens . pretty) (list . map (parens . pretty)) (Right True)
+-- True
 instance Pretty2 Either where
     liftPretty2 prettyLeft _ prettyRight _ = either prettyLeft prettyRight
 

From 566b0dc4609391790f77fc5a5af64e5014e0ea1f Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 23 Aug 2017 10:34:27 -0400
Subject: [PATCH 31/57] :memo: Pretty1 (Either a).

---
 prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index a269f0f9..1f532905 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -396,6 +396,13 @@ instance Pretty1 NonEmpty where
 instance Pretty1 Maybe where
     liftPretty prettyJust _ = maybe mempty prettyJust
 
+-- | Print 'Left' contents with 'pretty', and 'Right' contents with the supplied
+-- function.
+--
+-- >>> liftPretty (parens . pretty) (list . map (parens . pretty)) (Left True)
+-- True
+-- >>> liftPretty (parens . pretty) (list . map (parens . pretty)) (Right True)
+-- (True)
 instance Pretty a => Pretty1 (Either a) where
     liftPretty prettyRight _ = either pretty prettyRight
 

From 2fa9adce1c3d881ca08c84ce965f3e28574f6b21 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 23 Aug 2017 10:37:19 -0400
Subject: [PATCH 32/57] Better docs for Pretty1/Pretty2.

---
 .../src/Data/Text/Prettyprint/Doc/Internal.hs  | 18 ++++++++++++------
 1 file changed, 12 insertions(+), 6 deletions(-)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index 1f532905..28deb118 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -363,9 +363,12 @@ instance Pretty Void where pretty = absurd
 
 -- | Overloaded conversion to 'Doc', lifted to unary type constructors.
 --
--- This is most useful for defining 'Pretty' instances for recursive types, and
--- for efficiently pretty-printing 'Functor's whose definitions of 'fmap' don’t
--- fuse.
+-- This is most useful for:
+-- 1. defining 'Pretty' instances for recursive types,
+-- 2. defining 'Pretty' instances for type constructors without 'Functor'
+--    instances, and
+-- 3. efficiently pretty-printing type constructors with 'Functor' instances
+--    whose 'fmap' traverses the whole structure.
 --
 -- Laws:
 --
@@ -413,9 +416,12 @@ instance Pretty a => Pretty1 ((,) a) where
 
 -- | Overloaded conversion to 'Doc', lifted to binary type constructors.
 --
--- This is most useful for defining 'Pretty' instances for recursive types, and
--- for efficiently pretty-printing 'Functor's whose definitions of 'fmap' don’t
--- fuse.
+-- This is most useful for:
+-- 1. defining 'Pretty' instances for recursive types,
+-- 2. defining 'Pretty' instances for type constructors without 'Functor'
+--    instances, and
+-- 3. efficiently pretty-printing type constructors with 'Functor' instances
+--    whose 'fmap' traverses the whole structure.
 --
 -- Laws:
 --

From 21a3c33579e950d1ba5f13460b943011878f1684 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 23 Aug 2017 10:37:47 -0400
Subject: [PATCH 33/57] Correct the examples for Pretty2 Either.

---
 prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index 28deb118..ca9aec4f 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -437,10 +437,10 @@ class Pretty2 f where
 
 -- | Print 'Left' and 'Right' contents with the supplied functions.
 --
--- >>> liftPretty (parens . pretty) (list . map (parens . pretty)) (Left True)
--- True
--- >>> liftPretty (parens . pretty) (list . map (parens . pretty)) (Right True)
--- True
+-- >>> liftPretty2 (parens . pretty) (list . map (parens . pretty)) (parens . pretty) (list . map (parens . pretty)) (Left True)
+-- (True)
+-- >>> liftPretty2 (parens . pretty) (list . map (parens . pretty)) (parens . pretty) (list . map (parens . pretty)) (Right True)
+-- (True)
 instance Pretty2 Either where
     liftPretty2 prettyLeft _ prettyRight _ = either prettyLeft prettyRight
 

From 605f59a793533eabb8a1ef4b6d826b5672582a4c Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 23 Aug 2017 10:38:36 -0400
Subject: [PATCH 34/57] Match the formatting style of e.g. 'nest'.

---
 prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index ca9aec4f..d29d6716 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -377,7 +377,8 @@ class Pretty1 f where
 
     -- | >>> liftPretty (parens . pretty) (list . map (parens . pretty)) (Just "hello")
     -- (hello)
-    liftPretty :: (a -> Doc ann)
+    liftPretty
+               :: (a -> Doc ann)
                -> ([a] -> Doc ann)
                -> f a
                -> Doc ann
@@ -428,7 +429,8 @@ instance Pretty a => Pretty1 ((,) a) where
 --   1. output should be pretty. :-)
 class Pretty2 f where
 
-    liftPretty2 :: (a -> Doc ann)
+    liftPretty2
+                :: (a -> Doc ann)
                 -> ([a] -> Doc ann)
                 -> (b -> Doc ann)
                 -> ([b] -> Doc ann)

From ad6f1719518be86e524b9bf5727aef322f6129a6 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 23 Aug 2017 10:40:53 -0400
Subject: [PATCH 35/57] :memo: the arguments to liftPretty.

---
 prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index d29d6716..dd4622ac 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -378,8 +378,8 @@ class Pretty1 f where
     -- | >>> liftPretty (parens . pretty) (list . map (parens . pretty)) (Just "hello")
     -- (hello)
     liftPretty
-               :: (a -> Doc ann)
-               -> ([a] -> Doc ann)
+               :: (a -> Doc ann)   -- ^ A function to print a single value.
+               -> ([a] -> Doc ann) -- ^ A function to print a list. Used for [].
                -> f a
                -> Doc ann
 

From 07986b773a658bc626f34e269afd327a6a6f24ec Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 23 Aug 2017 10:41:16 -0400
Subject: [PATCH 36/57] =?UTF-8?q?Indent,=20don=E2=80=99t=20align.?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../src/Data/Text/Prettyprint/Doc/Internal.hs | 20 +++++++++----------
 1 file changed, 10 insertions(+), 10 deletions(-)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index dd4622ac..c1567c29 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -378,10 +378,10 @@ class Pretty1 f where
     -- | >>> liftPretty (parens . pretty) (list . map (parens . pretty)) (Just "hello")
     -- (hello)
     liftPretty
-               :: (a -> Doc ann)   -- ^ A function to print a single value.
-               -> ([a] -> Doc ann) -- ^ A function to print a list. Used for [].
-               -> f a
-               -> Doc ann
+        :: (a -> Doc ann)   -- ^ A function to print a single value.
+        -> ([a] -> Doc ann) -- ^ A function to print a list. Used for [].
+        -> f a
+        -> Doc ann
 
 -- | >>> liftPretty (parens . pretty) (list . map (parens . pretty)) [1,2,3]
 -- [(1), (2), (3)]
@@ -430,12 +430,12 @@ instance Pretty a => Pretty1 ((,) a) where
 class Pretty2 f where
 
     liftPretty2
-                :: (a -> Doc ann)
-                -> ([a] -> Doc ann)
-                -> (b -> Doc ann)
-                -> ([b] -> Doc ann)
-                -> f a b
-                -> Doc ann
+        :: (a -> Doc ann)
+        -> ([a] -> Doc ann)
+        -> (b -> Doc ann)
+        -> ([b] -> Doc ann)
+        -> f a b
+        -> Doc ann
 
 -- | Print 'Left' and 'Right' contents with the supplied functions.
 --

From 1da038bfe72ca45a3551733f8151274971c557dd Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 23 Aug 2017 10:43:35 -0400
Subject: [PATCH 37/57] :memo: the arguments to liftPretty2.

---
 prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index c1567c29..dc7bc3f4 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -430,10 +430,10 @@ instance Pretty a => Pretty1 ((,) a) where
 class Pretty2 f where
 
     liftPretty2
-        :: (a -> Doc ann)
-        -> ([a] -> Doc ann)
-        -> (b -> Doc ann)
-        -> ([b] -> Doc ann)
+        :: (a -> Doc ann)   -- ^ A function to print a single value of the first parameter.
+        -> ([a] -> Doc ann) -- ^ A function to print a list of the first parameter.
+        -> (b -> Doc ann)   -- ^ A function to print a single value of the second parameter.
+        -> ([b] -> Doc ann) -- ^ A function to print a list of the second parameter.
         -> f a b
         -> Doc ann
 

From f91663ae99be4474fb05b4276df43ed00da75c46 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 23 Aug 2017 10:48:48 -0400
Subject: [PATCH 38/57] Disambiguate the types for the doctests.

---
 prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index dc7bc3f4..c5948e99 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -403,9 +403,9 @@ instance Pretty1 Maybe where
 -- | Print 'Left' contents with 'pretty', and 'Right' contents with the supplied
 -- function.
 --
--- >>> liftPretty (parens . pretty) (list . map (parens . pretty)) (Left True)
+-- >>> liftPretty (parens . pretty) (list . map (parens . pretty)) (Left True :: Either Bool Bool)
 -- True
--- >>> liftPretty (parens . pretty) (list . map (parens . pretty)) (Right True)
+-- >>> liftPretty (parens . pretty) (list . map (parens . pretty)) (Right True :: Either Bool Bool)
 -- (True)
 instance Pretty a => Pretty1 (Either a) where
     liftPretty prettyRight _ = either pretty prettyRight
@@ -439,9 +439,9 @@ class Pretty2 f where
 
 -- | Print 'Left' and 'Right' contents with the supplied functions.
 --
--- >>> liftPretty2 (parens . pretty) (list . map (parens . pretty)) (parens . pretty) (list . map (parens . pretty)) (Left True)
+-- >>> liftPretty2 (parens . pretty) (list . map (parens . pretty)) (parens . pretty) (list . map (parens . pretty)) (Left True :: Either Bool Bool)
 -- (True)
--- >>> liftPretty2 (parens . pretty) (list . map (parens . pretty)) (parens . pretty) (list . map (parens . pretty)) (Right True)
+-- >>> liftPretty2 (parens . pretty) (list . map (parens . pretty)) (parens . pretty) (list . map (parens . pretty)) (Right True :: Either Bool Bool)
 -- (True)
 instance Pretty2 Either where
     liftPretty2 prettyLeft _ prettyRight _ = either prettyLeft prettyRight

From ee66301665ddfd7caf183c9591b769af8b67863a Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 23 Aug 2017 10:50:04 -0400
Subject: [PATCH 39/57] Fix the doctests for Pretty (Either a b).

---
 prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index c5948e99..9338a0ab 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -330,9 +330,9 @@ instance Pretty a => Pretty (Maybe a) where
 
 -- | Print 'Left' and 'Right' contents.
 --
--- >>> pretty (Left True)
+-- >>> pretty (Left True :: Either Bool Bool)
 -- True
--- >>> pretty (Right True)
+-- >>> pretty (Right True :: Either Bool Bool)
 -- True
 instance (Pretty a, Pretty b) => Pretty (Either a b) where
     pretty = either pretty pretty

From ec0e4825b18b5d43511396b03aac12b388c4ee02 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 23 Aug 2017 11:46:56 -0400
Subject: [PATCH 40/57] Export Pretty1 & Pretty2.

---
 prettyprinter/src/Data/Text/Prettyprint/Doc.hs | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc.hs
index 78661e17..dde12e17 100644
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc.hs
@@ -267,6 +267,10 @@ module Data.Text.Prettyprint.Doc (
     PageWidth(..), LayoutOptions(..), defaultLayoutOptions,
     layoutPretty, layoutCompact, layoutSmart,
 
+    -- * Lifted classes.
+    Pretty1(..),
+    Pretty2(..),
+
     -- * Migration guide
     --
     -- $migration

From fc5efc1d5d6c6377861a1f10bb934ef7a6125b49 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Sat, 26 Aug 2017 16:37:45 -0400
Subject: [PATCH 41/57] Reformat the doctests for the Pretty2 instance for
 Either.

---
 prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index 9338a0ab..41669b50 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -439,9 +439,13 @@ class Pretty2 f where
 
 -- | Print 'Left' and 'Right' contents with the supplied functions.
 --
--- >>> liftPretty2 (parens . pretty) (list . map (parens . pretty)) (parens . pretty) (list . map (parens . pretty)) (Left True :: Either Bool Bool)
+-- >>> let parenthesized = parens . pretty
+-- >>>     parenthesizedList = list . map parenthesized
+-- >>> liftPretty2 parenthesized parenthesizedList parenthesized parenthesizedList (Left True :: Either Bool Bool)
 -- (True)
--- >>> liftPretty2 (parens . pretty) (list . map (parens . pretty)) (parens . pretty) (list . map (parens . pretty)) (Right True :: Either Bool Bool)
+-- >>> let parenthesized = parens . pretty
+-- >>>     parenthesizedList = list . map parenthesized
+-- >>> liftPretty2 parenthesized parenthesizedList parenthesized parenthesizedList (Right True :: Either Bool Bool)
 -- (True)
 instance Pretty2 Either where
     liftPretty2 prettyLeft _ prettyRight _ = either prettyLeft prettyRight

From a60ab84a5ef59f3cbd46af46b7798b6052865602 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Sat, 26 Aug 2017 16:40:04 -0400
Subject: [PATCH 42/57] Give laws relating Pretty2, Pretty1, & Pretty.

---
 prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index 41669b50..71ea9d50 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -372,7 +372,7 @@ instance Pretty Void where pretty = absurd
 --
 -- Laws:
 --
---   1. output should be pretty. :-)
+--   1. liftPretty pretty prettyList f = pretty f
 class Pretty1 f where
 
     -- | >>> liftPretty (parens . pretty) (list . map (parens . pretty)) (Just "hello")
@@ -426,7 +426,8 @@ instance Pretty a => Pretty1 ((,) a) where
 --
 -- Laws:
 --
---   1. output should be pretty. :-)
+--   1. liftPretty2 pretty prettyList p pl f = liftPretty p pl f
+--   2. liftPretty2 pretty prettyList pretty prettyList f = pretty f
 class Pretty2 f where
 
     liftPretty2

From d6c2166af133a9272d01397baecc7c4f5d7f0416 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Sat, 26 Aug 2017 16:51:38 -0400
Subject: [PATCH 43/57] Better formatting of the laws.

---
 .../src/Data/Text/Prettyprint/Doc/Internal.hs      | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index 71ea9d50..e938051c 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -372,7 +372,11 @@ instance Pretty Void where pretty = absurd
 --
 -- Laws:
 --
---   1. liftPretty pretty prettyList f = pretty f
+--   1. @'Pretty1' f@ and @'Pretty' (f a)@ should result in identical behaviour:
+--
+--      @
+--      liftPretty pretty prettyList f = pretty f
+--      @
 class Pretty1 f where
 
     -- | >>> liftPretty (parens . pretty) (list . map (parens . pretty)) (Just "hello")
@@ -426,8 +430,12 @@ instance Pretty a => Pretty1 ((,) a) where
 --
 -- Laws:
 --
---   1. liftPretty2 pretty prettyList p pl f = liftPretty p pl f
---   2. liftPretty2 pretty prettyList pretty prettyList f = pretty f
+--   1. @'Pretty2' f@, @'Pretty1' (f a)@, and @'Pretty' (f a b)@ should result
+--      in identical behaviour:
+--
+--      @
+--      liftPretty2 pretty prettyList pretty prettyList f = liftPretty pretty prettyList f = pretty f
+--      @
 class Pretty2 f where
 
     liftPretty2

From 2441649f6b4c15584a99738a3d3a563251f56f75 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Sat, 26 Aug 2017 17:25:54 -0400
Subject: [PATCH 44/57] Fix the doctests.

---
 prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index e938051c..7e8e90f2 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -449,11 +449,11 @@ class Pretty2 f where
 -- | Print 'Left' and 'Right' contents with the supplied functions.
 --
 -- >>> let parenthesized = parens . pretty
--- >>>     parenthesizedList = list . map parenthesized
+-- >>> let parenthesizedList = list . map parenthesized
 -- >>> liftPretty2 parenthesized parenthesizedList parenthesized parenthesizedList (Left True :: Either Bool Bool)
 -- (True)
 -- >>> let parenthesized = parens . pretty
--- >>>     parenthesizedList = list . map parenthesized
+-- >>> let parenthesizedList = list . map parenthesized
 -- >>> liftPretty2 parenthesized parenthesizedList parenthesized parenthesizedList (Right True :: Either Bool Bool)
 -- (True)
 instance Pretty2 Either where

From 2284f72c53024866f37633392d12fcdaafa4fbc6 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 11 Oct 2017 11:17:24 -0400
Subject: [PATCH 45/57] :fire: the list parameters to liftPretty & liftPretty2.

---
 .../src/Data/Text/Prettyprint/Doc/Internal.hs | 42 ++++++++-----------
 1 file changed, 18 insertions(+), 24 deletions(-)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index 7e8e90f2..1b65783b 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -379,45 +379,44 @@ instance Pretty Void where pretty = absurd
 --      @
 class Pretty1 f where
 
-    -- | >>> liftPretty (parens . pretty) (list . map (parens . pretty)) (Just "hello")
+    -- | >>> liftPretty (parens . pretty) (Just "hello")
     -- (hello)
     liftPretty
-        :: (a -> Doc ann)   -- ^ A function to print a single value.
-        -> ([a] -> Doc ann) -- ^ A function to print a list. Used for [].
+        :: (a -> Doc ann)   -- ^ A function to print a value.
         -> f a
         -> Doc ann
 
--- | >>> liftPretty (parens . pretty) (list . map (parens . pretty)) [1,2,3]
+-- | >>> liftPretty (parens . pretty) [1,2,3]
 -- [(1), (2), (3)]
 instance Pretty1 [] where
-    liftPretty _ prettyList' = prettyList'
+    liftPretty pretty' = list . map pretty'
 
 instance Pretty1 NonEmpty where
-    liftPretty _ prettyList' (x:|xs) = prettyList' (x:xs)
+    liftPretty pretty' (x:|xs) = liftPretty pretty' (x:xs)
 
 -- | Ignore 'Nothing's, print 'Just' contents with the supplied function.
 --
--- >>> liftPretty (parens . pretty) (list . map (parens . pretty)) (Just True)
+-- >>> liftPretty (parens . pretty) (Just True)
 -- (True)
--- >>> braces (liftPretty (parens . pretty) (list . map (parens . pretty)) (Nothing :: Maybe Bool))
+-- >>> braces (liftPretty (parens . pretty) (Nothing :: Maybe Bool))
 -- {}
 instance Pretty1 Maybe where
-    liftPretty prettyJust _ = maybe mempty prettyJust
+    liftPretty prettyJust = maybe mempty prettyJust
 
 -- | Print 'Left' contents with 'pretty', and 'Right' contents with the supplied
 -- function.
 --
--- >>> liftPretty (parens . pretty) (list . map (parens . pretty)) (Left True :: Either Bool Bool)
+-- >>> liftPretty (parens . pretty) (Left True :: Either Bool Bool)
 -- True
--- >>> liftPretty (parens . pretty) (list . map (parens . pretty)) (Right True :: Either Bool Bool)
+-- >>> liftPretty (parens . pretty) (Right True :: Either Bool Bool)
 -- (True)
 instance Pretty a => Pretty1 (Either a) where
-    liftPretty prettyRight _ = either pretty prettyRight
+    liftPretty prettyRight = either pretty prettyRight
 
--- | >>> liftPretty (parens . pretty) (list . map (parens . pretty)) (123, "hello")
+-- | >>> liftPretty (parens . pretty) (123, "hello")
 -- (123, (hello))
 instance Pretty a => Pretty1 ((,) a) where
-    liftPretty pretty2 _ (x1, x2) = tupled [pretty x1, pretty2 x2]
+    liftPretty pretty2 (x1, x2) = tupled [pretty x1, pretty2 x2]
 
 -- | Overloaded conversion to 'Doc', lifted to binary type constructors.
 --
@@ -440,29 +439,24 @@ class Pretty2 f where
 
     liftPretty2
         :: (a -> Doc ann)   -- ^ A function to print a single value of the first parameter.
-        -> ([a] -> Doc ann) -- ^ A function to print a list of the first parameter.
         -> (b -> Doc ann)   -- ^ A function to print a single value of the second parameter.
-        -> ([b] -> Doc ann) -- ^ A function to print a list of the second parameter.
         -> f a b
         -> Doc ann
 
 -- | Print 'Left' and 'Right' contents with the supplied functions.
 --
 -- >>> let parenthesized = parens . pretty
--- >>> let parenthesizedList = list . map parenthesized
--- >>> liftPretty2 parenthesized parenthesizedList parenthesized parenthesizedList (Left True :: Either Bool Bool)
+-- >>> liftPretty2 parenthesized parenthesized (Left True :: Either Bool Bool)
 -- (True)
--- >>> let parenthesized = parens . pretty
--- >>> let parenthesizedList = list . map parenthesized
--- >>> liftPretty2 parenthesized parenthesizedList parenthesized parenthesizedList (Right True :: Either Bool Bool)
+-- >>> liftPretty2 parenthesized parenthesized (Right True :: Either Bool Bool)
 -- (True)
 instance Pretty2 Either where
-    liftPretty2 prettyLeft _ prettyRight _ = either prettyLeft prettyRight
+    liftPretty2 prettyLeft prettyRight = either prettyLeft prettyRight
 
--- | >>> liftPretty2 (parens . pretty) (list . map (parens . pretty)) (parens . pretty) (list . map (parens . pretty)) (123, "hello")
+-- | >>> liftPretty2 (parens . pretty) (parens . pretty) (123, "hello")
 -- ((123), (hello))
 instance Pretty2 (,) where
-    liftPretty2 pretty1 _ pretty2 _ (x1, x2) = tupled [pretty1 x1, pretty2 x2]
+    liftPretty2 pretty1 pretty2 (x1, x2) = tupled [pretty1 x1, pretty2 x2]
 
 -- | @(unsafeTextWithoutNewlines s)@ contains the literal string @s@.
 --

From d9425eb58c0f393628f94a08d22b7653cf7647d2 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 11 Oct 2017 11:17:48 -0400
Subject: [PATCH 46/57] Briefer docs for liftPretty2.

---
 prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index 1b65783b..36c9430f 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -438,8 +438,8 @@ instance Pretty a => Pretty1 ((,) a) where
 class Pretty2 f where
 
     liftPretty2
-        :: (a -> Doc ann)   -- ^ A function to print a single value of the first parameter.
-        -> (b -> Doc ann)   -- ^ A function to print a single value of the second parameter.
+        :: (a -> Doc ann)   -- ^ A function to print a value of the first parameter.
+        -> (b -> Doc ann)   -- ^ A function to print a value of the second parameter.
         -> f a b
         -> Doc ann
 

From 5b9f66b8f124404d30878f21d5679ecda10f5545 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 11 Oct 2017 11:22:07 -0400
Subject: [PATCH 47/57] Correct the law for Pretty1.

---
 prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index 36c9430f..84479235 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -372,10 +372,11 @@ instance Pretty Void where pretty = absurd
 --
 -- Laws:
 --
---   1. @'Pretty1' f@ and @'Pretty' (f a)@ should result in identical behaviour:
+--   1. @'Pretty1' f@ and @'Pretty' (f a)@ should result in identical behaviour
+--      when @'prettyList' = 'list' . map 'pretty'@ (the default definition):
 --
 --      @
---      liftPretty pretty prettyList f = pretty f
+--      liftPretty pretty f = pretty f
 --      @
 class Pretty1 f where
 

From 4dced207f57ca67296f309eb3e600493e5ab1ca3 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 11 Oct 2017 11:22:23 -0400
Subject: [PATCH 48/57] Note the difference in behaviour between Pretty1 and
 Pretty for [].

---
 prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index 84479235..cfa58aab 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -378,6 +378,13 @@ instance Pretty Void where pretty = absurd
 --      @
 --      liftPretty pretty f = pretty f
 --      @
+--
+-- Note that since 'liftPretty' does not receive a function corresponding to
+-- 'prettyList', the behaviour will differ for '[]', 'Maybe', and other types
+-- whose instances customize 'prettyList':
+--
+-- >>> liftPretty pretty "hello"
+-- [h, e, l, l, o]
 class Pretty1 f where
 
     -- | >>> liftPretty (parens . pretty) (Just "hello")

From 31cf99b6ef94bf031fd8e8f643a20b3b373678f5 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 11 Oct 2017 11:23:16 -0400
Subject: [PATCH 49/57] Cast for the doctest.

---
 prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index cfa58aab..82c4fc20 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -383,7 +383,7 @@ instance Pretty Void where pretty = absurd
 -- 'prettyList', the behaviour will differ for '[]', 'Maybe', and other types
 -- whose instances customize 'prettyList':
 --
--- >>> liftPretty pretty "hello"
+-- >>> liftPretty pretty ("hello" :: String)
 -- [h, e, l, l, o]
 class Pretty1 f where
 

From 03a1ae2dfa0c1f053a03a63749f9db8a399d9046 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 11 Oct 2017 11:25:08 -0400
Subject: [PATCH 50/57] Clarify the relationship between liftPretty2,
 liftPretty, and pretty.

---
 prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index 82c4fc20..a59e2df1 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -437,11 +437,12 @@ instance Pretty a => Pretty1 ((,) a) where
 --
 -- Laws:
 --
---   1. @'Pretty2' f@, @'Pretty1' (f a)@, and @'Pretty' (f a b)@ should result
---      in identical behaviour:
+--   1. @'Pretty2' f@, @'Pretty1' (f a)@, and @'Pretty' (f a b)@ should result in
+--      identical behaviour when @'prettyList' = 'list' . map 'pretty'@ (the
+--      default definition):
 --
 --      @
---      liftPretty2 pretty prettyList pretty prettyList f = liftPretty pretty prettyList f = pretty f
+--      liftPretty2 pretty pretty f = liftPretty pretty f = pretty f
 --      @
 class Pretty2 f where
 

From a1d6c13aa0ea24b2c337ea36d333f73a799de48a Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 11 Oct 2017 11:26:10 -0400
Subject: [PATCH 51/57] Dedent the param docs.

---
 prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index a59e2df1..3e1c139b 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -390,7 +390,7 @@ class Pretty1 f where
     -- | >>> liftPretty (parens . pretty) (Just "hello")
     -- (hello)
     liftPretty
-        :: (a -> Doc ann)   -- ^ A function to print a value.
+        :: (a -> Doc ann) -- ^ A function to print a value.
         -> f a
         -> Doc ann
 
@@ -447,8 +447,8 @@ instance Pretty a => Pretty1 ((,) a) where
 class Pretty2 f where
 
     liftPretty2
-        :: (a -> Doc ann)   -- ^ A function to print a value of the first parameter.
-        -> (b -> Doc ann)   -- ^ A function to print a value of the second parameter.
+        :: (a -> Doc ann) -- ^ A function to print a value of the first parameter.
+        -> (b -> Doc ann) -- ^ A function to print a value of the second parameter.
         -> f a b
         -> Doc ann
 

From 234154cedd49295c6e6d3f473f6ce2e725b94da4 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 11 Oct 2017 11:32:31 -0400
Subject: [PATCH 52/57] Better docs for liftPretty.

---
 prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index 3e1c139b..22b80c21 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -387,7 +387,10 @@ instance Pretty Void where pretty = absurd
 -- [h, e, l, l, o]
 class Pretty1 f where
 
-    -- | >>> liftPretty (parens . pretty) (Just "hello")
+    -- | Pretty-print a container using the supplied function to print its
+    -- contents.
+    --
+    -- >>> liftPretty (parens . pretty) (Just "hello")
     -- (hello)
     liftPretty
         :: (a -> Doc ann) -- ^ A function to print a value.

From d80a5e593a150fcd1988fb8d39fedee1d14cab50 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 11 Oct 2017 11:33:10 -0400
Subject: [PATCH 53/57] Docs for liftPretty2.

---
 prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index 22b80c21..6a03c263 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -449,6 +449,11 @@ instance Pretty a => Pretty1 ((,) a) where
 --      @
 class Pretty2 f where
 
+    -- | Pretty-print a container using the supplied functions to print its
+    -- contents.
+    --
+    -- >>> liftPretty2 (parens . pretty) pretty (("hello", 0) :: (String, Int))
+    -- ((hello), 0)
     liftPretty2
         :: (a -> Doc ann) -- ^ A function to print a value of the first parameter.
         -> (b -> Doc ann) -- ^ A function to print a value of the second parameter.

From 821a8f5a6f414622c62de37129dfa8534f25144f Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 11 Oct 2017 11:43:07 -0400
Subject: [PATCH 54/57] Use a longer example to illustrate Pretty1/Pretty for
 recursive types.

---
 .../src/Data/Text/Prettyprint/Doc/Internal.hs        | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index 6a03c263..efe4f4ae 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -385,6 +385,18 @@ instance Pretty Void where pretty = absurd
 --
 -- >>> liftPretty pretty ("hello" :: String)
 -- [h, e, l, l, o]
+--
+-- ==== __Examples__
+--
+-- Using 'Pretty1' to provide a (decidable!) 'Pretty' instance for a recursive
+-- type:
+--
+-- >>> data Expr a = Plus a a | Times a a | Const Int
+-- >>> newtype Fix f = Fix (f (Fix f))
+-- >>> instance Pretty1 Expr where liftPretty p e = case e of { Plus a b -> parens (p a <+> pretty '+' <+> p b) ; Times a b -> p a <+> pretty '*' <+> p b ; Const i -> pretty i }
+-- >>> instance Pretty1 f => Pretty (Fix f) where pretty (Fix f) = liftPretty pretty f
+-- >>> pretty (Fix (Times (Fix (Plus (Fix (Const 1)) (Fix (Const 2)))) (Fix (Const 3))))
+-- (1 + 2) * 3
 class Pretty1 f where
 
     -- | Pretty-print a container using the supplied function to print its

From 12457a84b555cf33820b2e922516f130366b90df Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 11 Oct 2017 11:44:15 -0400
Subject: [PATCH 55/57] Spacing.

---
 prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index efe4f4ae..12371163 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -393,8 +393,10 @@ instance Pretty Void where pretty = absurd
 --
 -- >>> data Expr a = Plus a a | Times a a | Const Int
 -- >>> newtype Fix f = Fix (f (Fix f))
+-- >>>
 -- >>> instance Pretty1 Expr where liftPretty p e = case e of { Plus a b -> parens (p a <+> pretty '+' <+> p b) ; Times a b -> p a <+> pretty '*' <+> p b ; Const i -> pretty i }
 -- >>> instance Pretty1 f => Pretty (Fix f) where pretty (Fix f) = liftPretty pretty f
+-- >>>
 -- >>> pretty (Fix (Times (Fix (Plus (Fix (Const 1)) (Fix (Const 2)))) (Fix (Const 3))))
 -- (1 + 2) * 3
 class Pretty1 f where

From dba8a03bf3320dd0115091c487430f7e76e8af15 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 11 Oct 2017 11:55:46 -0400
Subject: [PATCH 56/57] Split up the instances over multiple lines.

---
 .../src/Data/Text/Prettyprint/Doc/Internal.hs    | 16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index 12371163..2aaf2584 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -393,10 +393,18 @@ instance Pretty Void where pretty = absurd
 --
 -- >>> data Expr a = Plus a a | Times a a | Const Int
 -- >>> newtype Fix f = Fix (f (Fix f))
--- >>>
--- >>> instance Pretty1 Expr where liftPretty p e = case e of { Plus a b -> parens (p a <+> pretty '+' <+> p b) ; Times a b -> p a <+> pretty '*' <+> p b ; Const i -> pretty i }
--- >>> instance Pretty1 f => Pretty (Fix f) where pretty (Fix f) = liftPretty pretty f
--- >>>
+-- >>> :{
+-- >>> instance Pretty1 Expr where
+-- >>>   liftPretty p (Plus  a b) = parens (p a <+> pretty '+' <+> p b)
+-- >>>   liftPretty p (Times a b) =         p a <+> pretty '*' <+> p b
+-- >>>   liftPretty _ (Const i)   = pretty i
+-- >>> :}
+--
+-- >>> :{
+-- >>> instance Pretty1 f => Pretty (Fix f) where
+-- >>>   pretty (Fix f) = liftPretty pretty f
+-- >>> :}
+--
 -- >>> pretty (Fix (Times (Fix (Plus (Fix (Const 1)) (Fix (Const 2)))) (Fix (Const 3))))
 -- (1 + 2) * 3
 class Pretty1 f where

From b36e30677ce7af736edda93b141b7909fa1ebb9a Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 11 Oct 2017 12:03:27 -0400
Subject: [PATCH 57/57] :fire: an exclamation point.

---
 prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
index 2aaf2584..32d999d7 100755
--- a/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
+++ b/prettyprinter/src/Data/Text/Prettyprint/Doc/Internal.hs
@@ -388,7 +388,7 @@ instance Pretty Void where pretty = absurd
 --
 -- ==== __Examples__
 --
--- Using 'Pretty1' to provide a (decidable!) 'Pretty' instance for a recursive
+-- Using 'Pretty1' to provide a (decidable) 'Pretty' instance for a recursive
 -- type:
 --
 -- >>> data Expr a = Plus a a | Times a a | Const Int