Follow hlint suggestion: Use infix for elem

Author: philderbeast

.hlint.yaml

@@ -45,7 +45,6 @@
 - ignore: {name: "Use fold"} # 1 hint
 - ignore: {name: "Use fromMaybe"} # 5 hints
 - ignore: {name: "Use fst"} # 2 hints
-- ignore: {name: "Use infix"} # 27 hints
 - ignore: {name: "Use lambda-case"} # 58 hints
 - ignore: {name: "Use list comprehension"} # 19 hints
 - ignore: {name: "Use list literal"} # 3 hints

Cabal/src/Distribution/PackageDescription/Check.hs

@@ -423,7 +423,7 @@ checkPackageDescription
     -- But it is OK for executables to have the same name.
     nsubs <- asksCM (pnSubLibs . ccNames)
     checkP
-      (elem (prettyShow pn) (prettyShow <$> nsubs))
+      (prettyShow pn `elem` (prettyShow <$> nsubs))
       (PackageBuildImpossible $ IllegalLibraryName pn)
 
     -- § Fields check.

Cabal/src/Distribution/PackageDescription/Check/Conditional.hs

@@ -92,7 +92,7 @@ annotateCondTree fs ta (CondNode a c bs) =
     -- \*off* by default.
     isPkgFlagCond :: Condition ConfVar -> Bool
     isPkgFlagCond (Lit _) = False
-    isPkgFlagCond (Var (PackageFlag f)) = elem f defOffFlags
+    isPkgFlagCond (Var (PackageFlag f)) = f `elem` defOffFlags
     isPkgFlagCond (Var _) = False
     isPkgFlagCond (CNot cn) = not (isPkgFlagCond cn)
     isPkgFlagCond (CAnd ca cb) = isPkgFlagCond ca || isPkgFlagCond cb

Cabal/src/Distribution/PackageDescription/Check/Target.hs

@@ -692,7 +692,7 @@ checkAutogenModules ams bi = do
   -- PackageBuildImpossible and not merely PackageDistInexcusable.
   checkSpecVer
     CabalSpecV3_12
-    (elem autoInfoModuleName allModsForAuto)
+    (autoInfoModuleName `elem` allModsForAuto)
     (PackageBuildImpossible CVAutogenPackageInfoGuard)
   where
     allModsForAuto :: [ModuleName]

Cabal/src/Distribution/Simple/GHC/Build/Link.hs

@@ -726,7 +726,7 @@ extractRtsInfo lbi =
 -- threaded RTS. This is used to determine which RTS to link against when
 -- building a foreign library with a GHC without support for @-flink-rts@.
 hasThreaded :: BuildInfo -> Bool
-hasThreaded bi = elem "-threaded" ghc
+hasThreaded bi = "-threaded" `elem` ghc
   where
     PerCompilerFlavor ghc _ = options bi
 

Cabal/src/Distribution/Simple/GHC/Build/Utils.hs

@@ -76,15 +76,15 @@ withDynFLib flib =
 
 -- | Is this file a C++ source file, i.e. ends with .cpp, .cxx, or .c++?
 isCxx :: FilePath -> Bool
-isCxx fp = elem (takeExtension fp) [".cpp", ".cxx", ".c++"]
+isCxx fp = takeExtension fp `elem` [".cpp", ".cxx", ".c++"]
 
 -- | Is this a C source file, i.e. ends with .c?
 isC :: FilePath -> Bool
-isC fp = elem (takeExtension fp) [".c"]
+isC fp = takeExtension fp `elem` [".c"]
 
 -- | FilePath has a Haskell extension: .hs or .lhs
 isHaskell :: FilePath -> Bool
-isHaskell fp = elem (takeExtension fp) [".hs", ".lhs"]
+isHaskell fp = takeExtension fp `elem` [".hs", ".lhs"]
 
 -- | Returns True if the modification date of the given source file is newer than
 -- the object file we last compiled for it, or if no object file exists yet.

Cabal/src/Distribution/Simple/GHCJS.hs

@@ -1243,11 +1243,11 @@ gbuildSources verbosity mbWorkDir pkgId specVer tmpDir bm =
         }
 
     isCxx :: FilePath -> Bool
-    isCxx fp = elem (takeExtension fp) [".cpp", ".cxx", ".c++"]
+    isCxx fp = takeExtension fp `elem` [".cpp", ".cxx", ".c++"]
 
 -- | FilePath has a Haskell extension: .hs or .lhs
 isHaskell :: FilePath -> Bool
-isHaskell fp = elem (takeExtension fp) [".hs", ".lhs"]
+isHaskell fp = takeExtension fp `elem` [".hs", ".lhs"]
 
 -- | Generic build function. See comment for 'GBuildMode'.
 gbuild
@@ -1787,7 +1787,7 @@ popThreadedFlag bi =
       PerCompilerFlavor (filter p ghc) ghcjs
 
     hasThreaded :: PerCompilerFlavor [String] -> Bool
-    hasThreaded (PerCompilerFlavor ghc _) = elem "-threaded" ghc
+    hasThreaded (PerCompilerFlavor ghc _) = "-threaded" `elem` ghc
 
 -- | Extracts a String representing a hash of the ABI of a built
 -- library.  It can fail if the library has not yet been built.

cabal-install/src/Distribution/Client/Types/AllowNewer.hs

@@ -214,7 +214,7 @@ isRelaxDeps RelaxDepsAll = True
 -- | A smarter 'RelaxedDepsSome', @*:*@ is the same as @all@.
 mkRelaxDepSome :: [RelaxedDep] -> RelaxDeps
 mkRelaxDepSome xs
-  | elem (RelaxedDep RelaxDepScopeAll RelaxDepModNone RelaxDepSubjectAll) xs =
+  | RelaxedDep RelaxDepScopeAll RelaxDepModNone RelaxDepSubjectAll `elem` xs =
       RelaxDepsAll
   | otherwise =
       RelaxDepsSome xs