Widen support to GHC-7.4...GHC-8.8

.hlint.yaml

@@ -26,6 +26,9 @@
 - ignore: {name: "Use first"}
 - ignore: {name: "Use second"}
 
+# Use LambdaCase -- we cannot, GHC-7.6+ feature
+- ignore: {name: "Use lambda-case"}
+
 # Not all 3-liners should be deduplicated
 - ignore: {name: Reduce duplication, within: Data.Text.Prettyprint.Doc.Render.Terminal.Internal}
 

aux/version-compatibility-macros.h

@@ -14,7 +14,8 @@
 #define MONOID_IN_PRELUDE               MIN_VERSION_base(4,8,0)
 #define NATURAL_IN_BASE                 MIN_VERSION_base(4,8,0)
 
-#define MONAD_FAIL                      MIN_VERSION_base(4,9,0)
 #define SEMIGROUP_IN_BASE               MIN_VERSION_base(4,9,0)
 
+#define NO_FAIL_IN_MONAD_MONAD_FAIL     MIN_VERSION_base(4,13,0)
+
 #endif

prettyprinter-ansi-terminal/prettyprinter-ansi-terminal.cabal

@@ -34,12 +34,11 @@ library
     default-language: Haskell2010
     other-extensions:
           CPP
-        , LambdaCase
         , OverloadedStrings
 
 
     build-depends:
-          base          >= 4.7 && < 5
+          base          >= 4.5 && < 5
         , ansi-terminal >= 0.4.0
         , text          >= 1.2
         , prettyprinter >= 1.1.1

prettyprinter-ansi-terminal/src/Data/Text/Prettyprint/Doc/Render/Terminal/Internal.hs

@@ -1,5 +1,4 @@
 {-# LANGUAGE CPP               #-}
-{-# LANGUAGE LambdaCase        #-}
 {-# LANGUAGE OverloadedStrings #-}
 
 #include "version-compatibility-macros.h"
@@ -26,7 +25,19 @@ import           System.IO              (Handle, hPutChar, stdout)
 import Data.Text.Prettyprint.Doc
 import Data.Text.Prettyprint.Doc.Render.Util.Panic
 
+#if !MIN_VERSION_base(4,6,0)
+modifyIORef' :: IORef a -> (a -> a) -> IO ()
+modifyIORef' ref f = do
+    x <- readIORef ref
+    let x' = f x
+    x' `seq` writeIORef ref x'
 
+modifySTRef' :: STRef s a -> (a -> a) -> ST s ()
+modifySTRef' ref f = do
+    x <- readSTRef ref
+    let x' = f x
+    x' `seq` writeSTRef ref x'
+#endif
 
 -- $setup
 --
@@ -110,15 +121,15 @@ renderLazy sdoc = runST (do
     outputRef <- newSTRef mempty
 
     let push x = modifySTRef' styleStackRef (x :)
-        unsafePeek = readSTRef styleStackRef >>= \case
+        unsafePeek = readSTRef styleStackRef >>= \tok -> case tok of
             []  -> panicPeekedEmpty
             x:_ -> pure x
-        unsafePop = readSTRef styleStackRef >>= \case
+        unsafePop = readSTRef styleStackRef >>= \tok -> case tok of
             []   -> panicPeekedEmpty
             x:xs -> writeSTRef styleStackRef xs >> pure x
         writeOutput x = modifySTRef outputRef (<> x)
 
-    let go = \case
+    let go = \sds -> case sds of
             SFail -> panicUncaughtFail
             SEmpty -> pure ()
             SChar c rest -> do
@@ -142,7 +153,7 @@ renderLazy sdoc = runST (do
                 writeOutput (TLB.fromText (styleToRawText newStyle))
                 go rest
     go sdoc
-    readSTRef styleStackRef >>= \case
+    readSTRef styleStackRef >>= \stack -> case stack of
         []  -> panicStyleStackFullyConsumed
         [_] -> fmap TLB.toLazyText (readSTRef outputRef)
         xs  -> panicStyleStackNotFullyConsumed (length xs) )
@@ -172,14 +183,14 @@ renderIO h sdoc = do
     styleStackRef <- newIORef [mempty]
 
     let push x = modifyIORef' styleStackRef (x :)
-        unsafePeek = readIORef styleStackRef >>= \case
+        unsafePeek = readIORef styleStackRef >>= \tok -> case tok of
             [] -> panicPeekedEmpty
             x:_ -> pure x
-        unsafePop = readIORef styleStackRef >>= \case
+        unsafePop = readIORef styleStackRef >>= \tok -> case tok of
             [] -> panicPeekedEmpty
             x:xs -> writeIORef styleStackRef xs >> pure x
 
-    let go = \case
+    let go = \sds -> case sds of
             SFail -> panicUncaughtFail
             SEmpty -> pure ()
             SChar c rest -> do
@@ -204,7 +215,7 @@ renderIO h sdoc = do
                 T.hPutStr h (styleToRawText newStyle)
                 go rest
     go sdoc
-    readIORef styleStackRef >>= \case
+    readIORef styleStackRef >>= \stack -> case stack of
         []  -> panicStyleStackFullyConsumed
         [_] -> pure ()
         xs  -> panicStyleStackNotFullyConsumed (length xs)
@@ -288,12 +299,12 @@ styleToRawText = T.pack . ANSI.setSGRCode . stylesToSgrs
         ]
 
     convertIntensity :: Intensity -> ANSI.ColorIntensity
-    convertIntensity = \case
+    convertIntensity = \i -> case i of
         Vivid -> ANSI.Vivid
         Dull  -> ANSI.Dull
 
     convertColor :: Color -> ANSI.Color
-    convertColor = \case
+    convertColor = \c -> case c of
         Black   -> ANSI.Black
         Red     -> ANSI.Red
         Green   -> ANSI.Green

prettyprinter-compat-annotated-wl-pprint/prettyprinter-compat-annotated-wl-pprint.cabal

@@ -33,6 +33,6 @@ library
     other-extensions: CPP
 
     build-depends:
-          base          >= 4.7 && < 5
+          base          >= 4.5 && < 5
         , text          >= 1.2
         , prettyprinter >= 1

prettyprinter-compat-annotated-wl-pprint/src/Text/PrettyPrint/Annotated/Leijen.hs

@@ -17,9 +17,11 @@ module Text.PrettyPrint.Annotated.Leijen {-# DEPRECATED "Compatibility module fo
 
 ) where
 
-
-
+#if MIN_VERSION_base(4,8,0)
 import Prelude hiding ((<$>))
+#else
+import Prelude
+#endif
 
 #if !(MONOID_IN_PRELUDE)
 import Data.Monoid hiding ((<>))

prettyprinter-compat-ansi-wl-pprint/prettyprinter-compat-ansi-wl-pprint.cabal

@@ -30,11 +30,10 @@ library
     default-language: Haskell2010
     other-extensions:
           CPP
-        , LambdaCase
         , OverloadedStrings
 
     build-depends:
-          base                        >= 4.7 && < 5 && < 5
+          base                        >= 4.5 && < 5 && < 5
         , text                        >= 1.2
         , prettyprinter               >= 1
         , prettyprinter-ansi-terminal >= 1.1

prettyprinter-compat-ansi-wl-pprint/src/Text/PrettyPrint/ANSI/Leijen.hs

@@ -1,3 +1,5 @@
+{-# LANGUAGE CPP #-}
+
 module Text.PrettyPrint.ANSI.Leijen {-# DEPRECATED "Compatibility module for users of ansi-wl-pprint - use Data.Text.Prettyprint.Doc instead" #-} (
 
     Doc, putDoc, hPutDoc, empty, char, text, (<>), nest, line, linebreak, group,
@@ -17,9 +19,11 @@ module Text.PrettyPrint.ANSI.Leijen {-# DEPRECATED "Compatibility module for use
 
 ) where
 
-
-
+#if MIN_VERSION_base(4,8,0)
 import Prelude hiding ((<$>))
+#else
+import Prelude
+#endif
 
 import           Data.Monoid
 import qualified Data.Text.Lazy as TL

prettyprinter-compat-wl-pprint/prettyprinter-compat-wl-pprint.cabal

@@ -30,10 +30,9 @@ library
     default-language: Haskell2010
     other-extensions:
           CPP
-        , LambdaCase
         , OverloadedStrings
 
     build-depends:
-          base          >= 4.7 && < 5
+          base          >= 4.5 && < 5
         , text          >= 1.2
         , prettyprinter >= 1

prettyprinter-compat-wl-pprint/src/Text/PrettyPrint/Leijen.hs

@@ -1,3 +1,5 @@
+{-# LANGUAGE CPP #-}
+
 module Text.PrettyPrint.Leijen {-# DEPRECATED "Compatibility module for users of wl-pprint - use Data.Text.Prettyprint.Doc instead" #-} (
 
     Doc, putDoc, hPutDoc, empty, char, text, (<>), nest, line, linebreak, group,
@@ -14,7 +16,11 @@ module Text.PrettyPrint.Leijen {-# DEPRECATED "Compatibility module for users of
 
 
 
+#if MIN_VERSION_base(4,8,0)
 import Prelude hiding ((<$>))
+#else
+import Prelude
+#endif
 
 import           Data.Monoid
 import qualified Data.Text.Lazy as TL

prettyprinter-convert-ansi-wl-pprint/prettyprinter-convert-ansi-wl-pprint.cabal

@@ -30,11 +30,10 @@ library
     default-language: Haskell2010
     other-extensions:
           CPP
-        , LambdaCase
         , OverloadedStrings
 
     build-depends:
-          base                        >= 4.7 && < 5
+          base                        >= 4.5 && < 5
         , text                        >= 1.2
         , prettyprinter               >= 1
         , prettyprinter-ansi-terminal >= 1.1.1

prettyprinter-convert-ansi-wl-pprint/src/Data/Text/Prettyprint/Convert/AnsiWlPprint.hs

@@ -1,5 +1,3 @@
-{-# LANGUAGE LambdaCase #-}
-
 -- | Convert back and forth between the 'Old.Doc' type of the @ansi-wl-pprint@
 -- and the 'New.Doc' of the prettyprinter package. Useful in order to use the
 -- @prettyprinter@ library together with another library that produces
@@ -34,7 +32,7 @@ import qualified Text.PrettyPrint.ANSI.Leijen.Internal              as Old
 
 -- | @ansi-wl-pprint ───▷ prettyprinter@
 fromAnsiWlPprint :: Old.Doc -> New.Doc NewTerm.AnsiStyle
-fromAnsiWlPprint = \case
+fromAnsiWlPprint = \doc -> case doc of
     Old.Fail     -> New.Fail
     Old.Empty    -> New.Empty
     Old.Char c   -> New.Char c
@@ -87,7 +85,7 @@ fromAnsiWlPprint = \case
 
 -- | @prettyprinter ───▷ ansi-wl-pprint@
 toAnsiWlPprint :: New.Doc NewTerm.AnsiStyle -> Old.Doc
-toAnsiWlPprint = \case
+toAnsiWlPprint = \doc -> case doc of
     New.Fail     -> Old.Fail
     New.Empty    -> Old.Empty
     New.Char c   -> Old.Char c

prettyprinter/bench/LargeOutput.hs

@@ -1,15 +1,15 @@
 {-# LANGUAGE DeriveGeneric     #-}
-{-# LANGUAGE LambdaCase        #-}
 {-# LANGUAGE OverloadedStrings #-}
 
 {-# OPTIONS_GHC -fno-warn-orphans #-}
 
 module Main (main) where
 
-
+import Prelude        ()
+import Prelude.Compat
 
 import           Control.DeepSeq
-import           Control.Monad
+import           Control.Monad.Compat
 import           Criterion
 import           Criterion.Main
 import           Data.Char
@@ -98,7 +98,7 @@ instance Pretty LambdaForm where
         prettyExp = (<+> pretty body)
 
 instance Pretty Expr where
-    pretty = \case
+    pretty = \expr -> case expr of
         Let binds body ->
             align (vsep [ "let" <+> align (pretty binds)
                         , "in" <+> pretty body ])
@@ -141,7 +141,7 @@ instance WL.Pretty LambdaForm where
         prettyExp = (WL.<+> WL.pretty body)
 
 instance WL.Pretty Expr where
-    pretty = \case
+    pretty = \expr -> case expr of
         Let binds body ->
             WL.align (WL.vsep [ "let" WL.<+> WL.align (WL.pretty binds)
                         , "in" WL.<+> WL.pretty body ])

prettyprinter/prettyprinter.cabal

@@ -56,20 +56,23 @@ library
     other-extensions:
           BangPatterns
         , CPP
-        , LambdaCase
         , OverloadedStrings
         , QuasiQuotes
         , DefaultSignatures
         , ScopedTypeVariables
 
     build-depends:
-          base >= 4.7 && < 5
+          base >= 4.5 && < 5
         , text >= 1.2
 
+    if !impl(ghc >= 7.6)
+        build-depends: ghc-prim
+
     if impl(ghc >= 8.0)
         ghc-options: -Wcompat
     if !impl(ghc >= 8.0)
         build-depends: semigroups >= 0.1
+        build-depends: fail >= 4.9.0.0 && < 4.10
     if !impl(ghc >= 7.10)
         build-depends: void
 
@@ -141,7 +144,7 @@ benchmark fusion
     hs-source-dirs: bench
     main-is: Fusion.hs
     build-depends:
-          base >= 4.7 && < 5
+          base >= 4.5 && < 5
         , prettyprinter
 
         , criterion      >= 1.1
@@ -152,11 +155,11 @@ benchmark fusion
         , ansi-wl-pprint >= 0.6
     ghc-options: -Wall -threaded -rtsopts -with-rtsopts=-N
     default-language: Haskell2010
-    other-extensions: NumDecimals, OverloadedStrings
+    other-extensions: OverloadedStrings
 
 benchmark faster-unsafe-text
     build-depends:
-          base >= 4.7 && < 5
+          base >= 4.5 && < 5
         , prettyprinter
 
         , criterion >= 1.1
@@ -171,7 +174,8 @@ benchmark faster-unsafe-text
 
 benchmark large-output
     build-depends:
-          base >= 4.7 && < 5
+          base >= 4.5 && < 5
+        , base-compat >=0.10.5 && <0.11
         , prettyprinter
         , ansi-wl-pprint
 
@@ -186,3 +190,9 @@ benchmark large-output
     ghc-options:         -threaded -rtsopts -with-rtsopts=-N -Wall
     default-language:    Haskell2010
     type:                exitcode-stdio-1.0
+
+    if !impl(ghc >= 7.6)
+        build-depends: ghc-prim
+
+    if !impl(ghc >= 8.0)
+        build-depends: semigroups