From https://github.com/goldfirere/glambda/commit/2a4ee2e4e85cf65bb01f72ad2eb0bc6bc82aaced
From: jrp2014 <jrp@dial.pipex.com>
Date: Tue, 12 Mar 2019 19:54:19 +0000
Subject: [PATCH] Some hlinting

--- a/src/Language/Glambda/Lex.hs
+++ b/src/Language/Glambda/Lex.hs
@@ -130,5 +130,5 @@ word_token = to_token <$> word
 
 -- | Lex one word
 word :: Lexer String
-word = ((:) <$> (letter <|> char '_') <*>
-                 (many (alphaNum <|> char '_')))
+word = (:) <$> (letter <|> char '_') <*>
+                 many (alphaNum <|> char '_')
--- a/src/Language/Glambda/Parse.hs
+++ b/src/Language/Glambda/Parse.hs
@@ -140,7 +140,7 @@ lam = do
   tok Colon
   typ <- ty
   tok Dot
-  e <- bind bound_var $ expr
+  e <- bind bound_var expr
   return (ULam typ e)
 
 cond :: Parser UExp
@@ -175,4 +175,4 @@ mul_op = mk_op <$> arith_op [uTimes, uDivide, uMod]
 bool_op = mk_op <$> arith_op [uLess, uLessE, uGreater, uGreaterE, uEquals]
 
 mk_op :: UArithOp -> UExp -> UExp -> UExp
-mk_op op = \e1 e2 -> UArith e1 op e2
+mk_op op e1 e2 = UArith e1 op e2
--- a/src/Language/Glambda/Pretty.hs
+++ b/src/Language/Glambda/Pretty.hs
@@ -84,7 +84,7 @@ defaultPretty = nest 2 . prettyExp defaultColoring topPrec
 
 -- | Print a variable
 prettyVar :: Coloring -> Int -> Doc
-prettyVar (Coloring _ bound) n = (nthDefault id n bound) (char '#' <> int n)
+prettyVar (Coloring _ bound) n = nthDefault id n bound (char '#' <> int n)
 
 -- | Print a lambda expression
 prettyLam :: PrettyExp exp => Coloring -> Prec -> Maybe Ty -> exp -> Doc
--- a/src/Language/Glambda/Repl.hs
+++ b/src/Language/Glambda/Repl.hs
@@ -103,8 +103,7 @@ runStmts str = reportErrors $ do
 
 -- | Run a sequence of statements, returning the new global variables
 doStmts :: [Statement] -> GlamE Globals
-doStmts []     = ask
-doStmts (s:ss) = doStmt s $ doStmts ss
+doStmts  = foldr doStmt ask
 
 -- | Run a 'Statement' and then run another action with the global
 -- variables built in the 'Statement'
@@ -128,7 +127,7 @@ type CommandTable = [(String, String -> Glam ())]
 dispatchCommand :: CommandTable -> String -> Glam ()
 dispatchCommand table line
   = case List.filter ((cmd `List.isPrefixOf`) . fst) table of
-      []            -> do printLine $ text "Unknown command:" <+> squotes (text cmd)
+      []            -> printLine $ text "Unknown command:" <+> squotes (text cmd)
       [(_, action)] -> action arg
       many          -> do printLine $ text "Ambiguous command:" <+> squotes (text cmd)
                           printLine $ text "Possibilities:" $$
--- a/tests/Tests/Check.hs
+++ b/tests/Tests/Check.hs
@@ -52,7 +52,7 @@ checkTestCases = [ ("1", Just ("1", IntTy, "1"))
 checkTests :: TestTree
 checkTests = testGroup "Typechecker" $
   List.map (\(expr_str, m_result) ->
-               testCase ("`" ++ expr_str ++ "'") $
+               testCase ("`" ++ expr_str ++ "'")
                (case flip runReader id_globals $ runExceptT $ do
                        uexp <- hoistEither $ Arrow.left text $ parseExp =<< lex expr_str
                        check uexp $ \sty exp -> return $
--- a/tests/Tests/Parse.hs
+++ b/tests/Tests/Parse.hs
@@ -35,7 +35,7 @@ parseTests :: TestTree
 parseTests = testGroup "Parser"
   [ testGroup "Success" $
     List.map (\(str, out) -> testCase ("`" ++ str ++ "'") $
-              (render $ plain $ pretty (parseExp =<< lex str)) @?=
+              render (plain $ pretty (parseExp =<< lex str)) @?=
                 ("Right " ++ out))
              parseTestCases
   , testGroup "Failure" $
--- a/tests/Tests/Util.hs
+++ b/tests/Tests/Util.hs
@@ -33,8 +33,8 @@ import Language.Haskell.TH
 import Control.Monad
 
 prettyError :: Pretty a => a -> a -> String
-prettyError exp act = (render $ text "Expected" <+> squotes (pretty exp) <> semi <+>
-                                text "got" <+> squotes (pretty act))
+prettyError exp act = render $ text "Expected" <+> squotes (pretty exp) <> semi <+>
+                                text "got" <+> squotes (pretty act)
 
 (@?=) :: (Eq a, Pretty a) => a -> a -> Assertion
 act @?= exp = (act == exp) @? prettyError exp act
@@ -45,7 +45,7 @@ exp @=? act = (act == exp) @? prettyError exp act
 $( do decs <- reifyInstances ''Eq [ConT ''ParseError]
       case decs of  -- GHC 7.6 eagerly typechecks the instance, sometimes
                     -- reporting a duplicate. Urgh. So we can't quote it.
-        [] -> liftM (:[]) $
+        [] -> fmap (:[]) $
               instanceD (return []) (appT (conT ''Eq) (conT ''ParseError))
                         [ valD (varP '(==)) (normalB [| (==) `on` show |]) [] ]
         _  -> return [] )