stop supporting older environment in particular GHC <8.6 and megapars…

…ec <7

.github/workflows/build.yaml

@@ -7,47 +7,28 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        ghc: ['8.0.2', '8.2.2', '8.4.4', '8.6.5', '8.8.4', '8.10.7', '9.0.2', '9.2.8', '9.4.8', '9.6.4']
+        ghc: ['8.6.5', '8.8.4', '8.10.7', '9.0.2', '9.2.8', '9.4.8', '9.6.4']
         os: [ubuntu-latest]
         include:
-          - ghc: '8.0.2'
-            stack: '2.13'  # Due to a bug, Stack 2.15.1 did not support versions of GHC before 8.2.
-            resolver: 'lts-9.21'
-            flags: ''
-          - ghc: '8.2.2'
-            stack: 'latest'
-            resolver: 'lts-11.22'
-            flags: ''
-          - ghc: '8.4.4'
-            stack: 'latest'
-            resolver: 'lts-12.26'
-            flags: ''
           - ghc: '8.6.5'
-            stack: 'latest'
             resolver: 'lts-14.27'
             flags: ''
           - ghc: '8.8.4'
-            stack: 'latest'
             resolver: 'lts-16.31'
             flags: ''
           - ghc: '8.10.7'
-            stack: 'latest'
             resolver: 'lts-18.28'
             flags: ''
           - ghc: '9.0.2'
-            stack: 'latest'
             resolver: 'lts-19.33'
             flags: ''
           - ghc: '9.2.8'
-            stack: 'latest'
             resolver: 'lts-20.26'
             flags: ''
           - ghc: '9.4.8'
-            stack: 'latest'
             resolver: 'lts-21.25'
             flags: ''
           - ghc: '9.6.4'
-            stack: 'latest'
             resolver: 'lts-22.13'
             coveralls: true
             flags: '--coverage'
@@ -59,7 +40,7 @@ jobs:
         with:
           ghc-version: ${{ matrix.ghc }}
           enable-stack: true
-          stack-version: ${{ matrix.stack }}
+          stack-version: latest
 
       - uses: actions/cache@v1
         name: Cache ~/.stack

pseudo-boolean.cabal

@@ -57,16 +57,15 @@ library
      FlexibleContexts
      OverloadedStrings
   build-depends:
-     base >=4.6.0.1 && <4.20,
-     containers >=0.4.2.1,
+     base >=4.12.0.0 && <4.20,
+     containers >=0.6.0.1,
      parsec >=3.1.2 && <4,
-     megaparsec >=4 && <10,
-     bytestring >=0.9.2.1 && <0.13,
-     bytestring-builder,
-     dlist >=0.7.0 && <1.1.0,
-     attoparsec >=0.10.4.0,
-     deepseq >=1.3.0.0,
-     hashable >=1.1.2.5 && <1.5.0.0,
+     megaparsec >=7 && <10,
+     bytestring >=0.10.8.2 && <0.13,
+     dlist >=0.8.0.5 && <1.1.0,
+     attoparsec >=0.13.2.2,
+     deepseq >=1.4.4.0,
+     hashable >=1.2.7.0 && <1.5.0.0,
      void
   hs-source-dirs:      src
   default-language:    Haskell2010

src/Data/PseudoBoolean/Internal/TextUtil.hs

@@ -31,12 +31,7 @@ readUnsignedInteger str = assert (result == read str) $ result
     result = go 0 str
 
     lim :: Word
-#if !MIN_VERSION_base(4,6,1) && WORD_SIZE_IN_BITS == 32
-    {- To avoid a bug of maxBound <https://ghc.haskell.org/trac/ghc/ticket/8072> -}
-    lim = 0xFFFFFFFF `div` 10
-#else
     lim = maxBound `div` 10
-#endif
 
     go :: Integer -> [Char] -> Integer 
     go !r [] = r

src/Data/PseudoBoolean/Megaparsec.hs

@@ -1,4 +1,4 @@
-{-# LANGUAGE BangPatterns, FlexibleContexts, TypeFamilies, CPP, ConstraintKinds #-}
+{-# LANGUAGE BangPatterns, FlexibleContexts, TypeFamilies, ConstraintKinds #-}
 {-# LANGUAGE OverloadedStrings #-}
 {-# LANGUAGE TypeOperators #-}
 {-# OPTIONS_GHC -Wall #-}
@@ -45,70 +45,29 @@ import Control.Monad
 import Data.ByteString.Lazy (ByteString)
 import qualified Data.ByteString.Lazy.Char8 as BL
 import Data.Maybe
-#if MIN_VERSION_megaparsec(6,0,0)
 import Data.String
 import Data.Word
 import Data.Void
-#endif
 import Text.Megaparsec hiding (ParseError)
 import qualified Text.Megaparsec as MP
-#if MIN_VERSION_megaparsec(6,0,0)
 import Text.Megaparsec.Byte
-#else
-import Text.Megaparsec.Prim (MonadParsec ())
-#endif
 import Data.PseudoBoolean.Types
 import Data.PseudoBoolean.Internal.TextUtil
 
-#if MIN_VERSION_megaparsec(6,0,0)
-
 type C e s m = (MonadParsec e s m, Token s ~ Word8, IsString (Tokens s))
 
 char8 :: C e s m => Char -> m Word8
 char8 = char . fromIntegral . fromEnum
 
-#else
-
-#if MIN_VERSION_megaparsec(5,0,0)
-type C e s m = (MonadParsec e s m, Token s ~ Char)
-#elif MIN_VERSION_megaparsec(4,4,0)
-type C e s m = (MonadParsec s m Char)
-#else
-type C e s m = (MonadParsec s m Char, MonadPlus m)
-#endif
-
-char8 :: C e s m => Char -> m Char
-char8 = char
-
-#endif
-
-#if MIN_VERSION_megaparsec(7,0,0)
 anyChar :: C e s m => m Word8
 anyChar = anySingle
-#endif
 
 -- | Parser for OPB files
-#if MIN_VERSION_megaparsec(6,0,0)
 opbParser :: (MonadParsec e s m, Token s ~ Word8, IsString (Tokens s)) => m Formula
-#elif MIN_VERSION_megaparsec(5,0,0)
-opbParser :: (MonadParsec e s m, Token s ~ Char) => m Formula
-#elif MIN_VERSION_megaparsec(4,4,0)
-opbParser :: (MonadParsec s m Char) => m Formula
-#else
-opbParser :: (MonadParsec s m Char, MonadPlus m) => m Formula
-#endif
 opbParser = formula
 
 -- | Parser for WBO files
-#if MIN_VERSION_megaparsec(6,0,0)
 wboParser :: (MonadParsec e s m, Token s ~ Word8, IsString (Tokens s)) => m SoftFormula
-#elif MIN_VERSION_megaparsec(5,0,0)
-wboParser :: (MonadParsec e s m, Token s ~ Char) => m SoftFormula
-#elif MIN_VERSION_megaparsec(4,4,0)
-wboParser :: (MonadParsec s m Char) => m SoftFormula
-#else
-wboParser :: (MonadParsec s m Char, MonadPlus m) => m SoftFormula
-#endif
 wboParser = softformula
 
 -- <formula>::= <sequence_of_comments> [<objective>] <sequence_of_comments_or_constraints>
@@ -208,11 +167,7 @@ integer = msum
 unsigned_integer :: C e s m => m Integer
 unsigned_integer = do
   ds <- some digitChar
-#if MIN_VERSION_megaparsec(6,0,0)
   return $! readUnsignedInteger (map (toEnum . fromIntegral) ds)
-#else
-  return $! readUnsignedInteger ds
-#endif
 
 -- <relational_operator>::= ">=" | "="
 relational_operator :: C e s m => m Op
@@ -262,23 +217,11 @@ oneOrMoreLiterals = do
 literal :: C e s m => m Lit
 literal = variablename <|> (char8 '~' >> liftM negate variablename)
 
-#if MIN_VERSION_megaparsec(7,0,0)
 type ParseError = MP.ParseErrorBundle BL.ByteString Void
-#elif MIN_VERSION_megaparsec(6,0,0)
-type ParseError = MP.ParseError Word8 Void
-#elif MIN_VERSION_megaparsec(5,0,0)
-type ParseError = MP.ParseError Char Dec
-#else
-type ParseError = MP.ParseError
-#endif
 
 -- | Parse a OPB format string containing pseudo boolean problem.
 parseOPBString :: String -> String -> Either ParseError Formula
-#if MIN_VERSION_megaparsec(6,0,0)
 parseOPBString info s = parse (formula <* eof) info (BL.pack s)
-#else
-parseOPBString = parse (formula <* eof)
-#endif
 
 -- | Parse a OPB format lazy bytestring containing pseudo boolean problem.
 parseOPBByteString :: String -> ByteString -> Either ParseError Formula
@@ -341,11 +284,7 @@ softconstraint = do
 
 -- | Parse a WBO format string containing weighted boolean optimization problem.
 parseWBOString :: String -> String -> Either ParseError SoftFormula
-#if MIN_VERSION_megaparsec(6,0,0)
 parseWBOString info s = parse (softformula <* eof) info (BL.pack s)
-#else
-parseWBOString = parse (softformula <* eof)
-#endif
 
 -- | Parse a WBO format lazy bytestring containing pseudo boolean problem.
 parseWBOByteString :: String -> ByteString -> Either ParseError SoftFormula