hlint code improvements.

42 files changed, 207 insertions, 234 deletions

diff --git a/src/Text/Pandoc/Class.hs b/src/Text/Pandoc/Class.hs
index f8d6b6737..ae538046a 100644
--- a/src/Text/Pandoc/Class.hs
+++ b/src/Text/Pandoc/Class.hs
@@ -142,11 +142,11 @@ import qualified System.Environment as IO (lookupEnv)
 import System.FilePath.Glob (match, compile)
 import System.Directory (createDirectoryIfMissing, getDirectoryContents,
                           doesDirectoryExist)
-import System.FilePath ((</>), (<.>), takeDirectory,
-         takeExtension, dropExtension, isRelative, normalise)
+import System.FilePath
+       ((</>), (<.>), takeDirectory, takeExtension, dropExtension,
+        isRelative, normalise, splitDirectories)
 import qualified System.FilePath.Glob as IO (glob)
 import qualified System.FilePath.Posix as Posix
-import System.FilePath (splitDirectories)
 import qualified System.Directory as IO (getModificationTime)
 import Control.Monad as M (fail)
 import Control.Monad.State.Strict
diff --git a/src/Text/Pandoc/Filter.hs b/src/Text/Pandoc/Filter.hs
index 67b3a5f2c..e2a3c3e16 100644
--- a/src/Text/Pandoc/Filter.hs
+++ b/src/Text/Pandoc/Filter.hs
@@ -51,7 +51,7 @@ applyFilters :: ReaderOptions
              -> [String]
              -> Pandoc
              -> PandocIO Pandoc
-applyFilters ropts filters args d = do
+applyFilters ropts filters args d =
   foldrM ($) d $ map applyFilter filters
  where
   applyFilter (JSONFilter f) = JSONFilter.apply ropts args f
diff --git a/src/Text/Pandoc/Lua.hs b/src/Text/Pandoc/Lua.hs
index edf803b45..790be47d5 100644
--- a/src/Text/Pandoc/Lua.hs
+++ b/src/Text/Pandoc/Lua.hs
@@ -65,7 +65,7 @@ runLuaFilter' ropts filterPath format pd = do
       newtop <- Lua.gettop
       -- Use the returned filters, or the implicitly defined global filter if
       -- nothing was returned.
-      luaFilters <- if (newtop - top >= 1)
+      luaFilters <- if newtop - top >= 1
                     then peek (-1)
                     else Lua.getglobal "_G" *> fmap (:[]) popValue
       runAll luaFilters pd
diff --git a/src/Text/Pandoc/Lua/Packages.hs b/src/Text/Pandoc/Lua/Packages.hs
index 0169d0045..1e6ff22fe 100644
--- a/src/Text/Pandoc/Lua/Packages.hs
+++ b/src/Text/Pandoc/Lua/Packages.hs
@@ -113,4 +113,3 @@ dataDirScript datadir moduleFile = do
   return $ case res of
     Left _ -> Nothing
     Right s -> Just (unpack s)
-
diff --git a/src/Text/Pandoc/Lua/StackInstances.hs b/src/Text/Pandoc/Lua/StackInstances.hs
index 38404157c..a504e5626 100644
--- a/src/Text/Pandoc/Lua/StackInstances.hs
+++ b/src/Text/Pandoc/Lua/StackInstances.hs
@@ -383,4 +383,3 @@ instance ToLuaStack ReaderOptions where
     LuaUtil.addValue "defaultImageExtension" defaultImageExtension
     LuaUtil.addValue "trackChanges" trackChanges
     LuaUtil.addValue "stripComments" stripComments
-
diff --git a/src/Text/Pandoc/Parsing.hs b/src/Text/Pandoc/Parsing.hs
index f1b823965..e87ea71da 100644
--- a/src/Text/Pandoc/Parsing.hs
+++ b/src/Text/Pandoc/Parsing.hs
@@ -189,12 +189,12 @@ where
 
 import Control.Monad.Identity
 import Control.Monad.Reader
-import Data.Char (chr, isAlphaNum, isAscii, isAsciiUpper, isHexDigit, isPunctuation, isSpace,
-                  ord, toLower, toUpper)
+import Data.Char (chr, isAlphaNum, isAscii, isAsciiUpper, isHexDigit,
+                  isPunctuation, isSpace, ord, toLower, toUpper)
 import Data.Default
 import Data.List (intercalate, isSuffixOf, transpose)
 import qualified Data.Map as M
-import Data.Maybe (mapMaybe)
+import Data.Maybe (mapMaybe, fromMaybe)
 import Data.Monoid ((<>))
 import qualified Data.Set as Set
 import Data.Text (Text)
@@ -304,7 +304,7 @@ indentWith :: Stream s m Char
            => Int -> ParserT s st m [Char]
 indentWith num = do
   tabStop <- getOption readerTabStop
-  if (num < tabStop)
+  if num < tabStop
      then count num (char ' ')
      else choice [ try (count num (char ' '))
                  , try (char '\t' >> indentWith (num - tabStop)) ]
@@ -573,7 +573,7 @@ uri = try $ do
   let uriChunk =  skipMany1 wordChar
               <|> percentEscaped
               <|> entity
-              <|> (try $ punct >>
+              <|> try (punct >>
                     lookAhead (void (satisfy isWordChar) <|> percentEscaped))
   str <- snd <$> withRaw (skipMany1 ( () <$
                                          (enclosed (char '(') (char ')') uriChunk
@@ -755,7 +755,7 @@ romanOne = (char 'i' >> return (LowerRoman, 1)) <|>
 
 -- | Parses an ordered list marker and returns list attributes.
 anyOrderedListMarker :: Stream s m Char => ParserT s ParserState m ListAttributes
-anyOrderedListMarker = choice $
+anyOrderedListMarker = choice
   [delimParser numParser | delimParser <- [inPeriod, inOneParen, inTwoParens],
                            numParser <- [decimal, exampleNum, defaultNum, romanOne,
                            lowerAlpha, lowerRoman, upperAlpha, upperRoman]]
@@ -896,7 +896,7 @@ widthsFromIndices numColumns' indices =
       quotient = if totLength > numColumns
                    then fromIntegral totLength
                    else fromIntegral numColumns
-      fracs = map (\l -> (fromIntegral l) / quotient) lengths in
+      fracs = map (\l -> fromIntegral l / quotient) lengths in
   tail fracs
 
 ---
@@ -977,7 +977,7 @@ gridTableHeader headless blocks = try $ do
                     then replicate (length underDashes) ""
                     else map (unlines . map trim) $ transpose
                        $ map (gridTableSplitLine indices) rawContent
-  heads <- fmap sequence $ mapM (parseFromString blocks . trim) rawHeads
+  heads <- sequence <$> mapM (parseFromString blocks . trim) rawHeads
   return (heads, aligns, indices)
 
 gridTableRawLine :: Stream s m Char => [Int] -> ParserT s st m [String]
@@ -1323,9 +1323,7 @@ failIfInQuoteContext :: (HasQuoteContext st m, Stream s m t)
                      -> ParserT s st m ()
 failIfInQuoteContext context = do
   context' <- getQuoteContext
-  if context' == context
-     then fail "already inside quotes"
-     else return ()
+  when (context' == context) $ fail "already inside quotes"
 
 charOrRef :: Stream s m Char => String -> ParserT s st m Char
 charOrRef cs =
@@ -1418,9 +1416,7 @@ a <+?> b = a >>= flip fmap (try b <|> return mempty) . (<>)
 extractIdClass :: Attr -> Attr
 extractIdClass (ident, cls, kvs) = (ident', cls', kvs')
   where
-    ident' = case lookup "id" kvs of
-               Just v  -> v
-               Nothing -> ident
+    ident' = fromMaybe ident (lookup "id" kvs)
     cls'   = case lookup "class" kvs of
                Just cl -> words cl
                Nothing -> cls
diff --git a/src/Text/Pandoc/Readers/Docx.hs b/src/Text/Pandoc/Readers/Docx.hs
index 21120824f..c24c43901 100644
--- a/src/Text/Pandoc/Readers/Docx.hs
+++ b/src/Text/Pandoc/Readers/Docx.hs
@@ -81,7 +81,7 @@ import qualified Data.ByteString.Lazy as B
 import Data.Default (Default)
 import Data.List (delete, intersect)
 import qualified Data.Map as M
-import Data.Maybe (isJust)
+import Data.Maybe (isJust, fromMaybe)
 import Data.Sequence (ViewL (..), viewl)
 import qualified Data.Sequence as Seq
 import qualified Data.Set as Set
@@ -187,7 +187,7 @@ bodyPartsToMeta' :: PandocMonad m => [BodyPart] -> DocxContext m (M.Map String M
 bodyPartsToMeta' [] = return M.empty
 bodyPartsToMeta' (bp : bps)
   | (Paragraph pPr parParts) <- bp
-  , (c : _)<- intersect (pStyle pPr) (M.keys metaStyles)
+  , (c : _)<- (pStyle pPr) `intersect` (M.keys metaStyles)
   , (Just metaField) <- M.lookup c metaStyles = do
     inlines <- smushInlines <$> mapM parPartToInlines parParts
     remaining <- bodyPartsToMeta' bps
@@ -340,7 +340,7 @@ blocksToInlinesWarn cmtId blks = do
       notParaOrPlain (Para _)  = False
       notParaOrPlain (Plain _) = False
       notParaOrPlain _         = True
-  unless (null $ filter notParaOrPlain blkList) $
+  unless ( not (any notParaOrPlain blkList)) $
     lift $ P.report $ DocxParserWarning $
       "Docx comment " ++ cmtId ++ " will not retain formatting"
   return $ blocksToInlines' blkList
@@ -351,7 +351,7 @@ blocksToInlinesWarn cmtId blks = do
 parPartToInlines :: PandocMonad m => ParPart -> DocxContext m Inlines
 parPartToInlines parPart =
   case parPart of
-    (BookMark _ anchor) | not $ anchor `elem` dummyAnchors -> do
+    (BookMark _ anchor) | notElem anchor dummyAnchors -> do
       inHdrBool <- asks docxInHeaderBlock
       ils <- parPartToInlines' parPart
       immedPrevAnchor <- gets docxImmedPrevAnchor
@@ -444,9 +444,9 @@ parPartToInlines' (ExternalHyperLink target runs) = do
   return $ link target "" ils
 parPartToInlines' (PlainOMath exps) =
   return $ math $ writeTeX exps
-parPartToInlines' (SmartTag runs) = do
+parPartToInlines' (SmartTag runs) =
   smushInlines <$> mapM runToInlines runs
-parPartToInlines' (Field info runs) = do
+parPartToInlines' (Field info runs) =
   case info of
     HyperlinkField url -> parPartToInlines' $ ExternalHyperLink url runs
     UnknownField -> smushInlines <$> mapM runToInlines runs
@@ -626,9 +626,7 @@ bodyPartToBlocks (ListItem pPr numId lvl (Just levelInfo) parparts) = do
       (_, fmt,txt, startFromLevelInfo) = levelInfo
       start = case startFromState of
         Just n -> n + 1
-        Nothing -> case startFromLevelInfo of
-          Just n' -> n'
-          Nothing -> 1
+        Nothing -> fromMaybe 1 startFromLevelInfo
       kvs = [ ("level", lvl)
             , ("num-id", numId)
             , ("format", fmt)
diff --git a/src/Text/Pandoc/Readers/Docx/Fields.hs b/src/Text/Pandoc/Readers/Docx/Fields.hs
index 69758b431..f0821a751 100644
--- a/src/Text/Pandoc/Readers/Docx/Fields.hs
+++ b/src/Text/Pandoc/Readers/Docx/Fields.hs
@@ -46,7 +46,7 @@ parseFieldInfo = parse fieldInfo ""
 
 fieldInfo :: Parser FieldInfo
 fieldInfo =
-  (try $ HyperlinkField <$> hyperlink)
+  try (HyperlinkField <$> hyperlink)
   <|>
   return UnknownField
 
@@ -54,7 +54,7 @@ escapedQuote :: Parser String
 escapedQuote = string "\\\""
 
 inQuotes :: Parser String
-inQuotes = do
+inQuotes =
   (try escapedQuote) <|> (anyChar >>= (\c -> return [c]))
 
 quotedString :: Parser String
@@ -63,7 +63,7 @@ quotedString = do
   concat <$> manyTill inQuotes (try (char '"'))
 
 unquotedString :: Parser String
-unquotedString = manyTill anyChar (try (space))
+unquotedString = manyTill anyChar (try space)
 
 fieldArgument :: Parser String
 fieldArgument = quotedString <|> unquotedString
@@ -82,7 +82,7 @@ hyperlink = do
   string "HYPERLINK"
   spaces
   farg <- fieldArgument
-  switches <- (spaces *> many hyperlinkSwitch)
+  switches <- spaces *> many hyperlinkSwitch
   let url = case switches of
               ("\\l", s) : _ -> farg ++ ('#': s)
               _              -> farg
diff --git a/src/Text/Pandoc/Readers/Docx/Lists.hs b/src/Text/Pandoc/Readers/Docx/Lists.hs
index fa4870fff..c0f05094a 100644
--- a/src/Text/Pandoc/Readers/Docx/Lists.hs
+++ b/src/Text/Pandoc/Readers/Docx/Lists.hs
@@ -44,14 +44,14 @@ isListItem (Div (_, classes, _) _) | "list-item" `elem` classes = True
 isListItem _                       = False
 
 getLevel :: Block -> Maybe Integer
-getLevel (Div (_, _, kvs) _) =  fmap read $ lookup "level" kvs
+getLevel (Div (_, _, kvs) _) =  read <$> lookup "level" kvs
 getLevel _                   = Nothing
 
 getLevelN :: Block -> Integer
 getLevelN b = fromMaybe (-1) (getLevel b)
 
 getNumId :: Block -> Maybe Integer
-getNumId (Div (_, _, kvs) _) =  fmap read $ lookup "num-id" kvs
+getNumId (Div (_, _, kvs) _) =  read <$> lookup "num-id" kvs
 getNumId _                   = Nothing
 
 getNumIdN :: Block -> Integer
@@ -140,8 +140,8 @@ flatToBullets' num xs@(b : elems)
         (children, remaining) =
           span
           (\b' ->
-            (getLevelN b') > bLevel ||
-             ((getLevelN b') == bLevel && (getNumIdN b') == bNumId))
+            getLevelN b' > bLevel ||
+             (getLevelN b' == bLevel && getNumIdN b' == bNumId))
           xs
     in
      case getListType b of
diff --git a/src/Text/Pandoc/Readers/Docx/Parse.hs b/src/Text/Pandoc/Readers/Docx/Parse.hs
index 5f648666f..c123a0018 100644
--- a/src/Text/Pandoc/Readers/Docx/Parse.hs
+++ b/src/Text/Pandoc/Readers/Docx/Parse.hs
@@ -358,9 +358,7 @@ archiveToDocument zf = do
   docElem <- maybeToD $ (parseXMLDoc . UTF8.toStringLazy . fromEntry) entry
   let namespaces = elemToNameSpaces docElem
   bodyElem <- maybeToD $ findChildByName namespaces "w" "body" docElem
-  let bodyElem' = case walkDocument namespaces bodyElem of
-        Just e -> e
-        Nothing -> bodyElem
+  let bodyElem' = fromMaybe bodyElem (walkDocument namespaces bodyElem)
   body <- elemToBody namespaces bodyElem'
   return $ Document namespaces body
 
@@ -603,7 +601,7 @@ elemToTblLook ns element | isElem ns "w" "tblLook" element =
             Just bitMask -> testBitMask bitMask 0x020
             Nothing      -> False
   in
-   return $ TblLook{firstRowFormatting = firstRowFmt}
+   return TblLook{firstRowFormatting = firstRowFmt}
 elemToTblLook _ _ = throwError WrongElem
 
 elemToRow :: NameSpaces -> Element -> D Row
@@ -623,7 +621,7 @@ elemToCell _ _ = throwError WrongElem
 
 elemToParIndentation :: NameSpaces -> Element -> Maybe ParIndentation
 elemToParIndentation ns element | isElem ns "w" "ind" element =
-  Just $ ParIndentation {
+ Just ParIndentation {
     leftParIndent =
        findAttrByName ns "w" "left" element >>=
        stringToInteger
@@ -1173,8 +1171,7 @@ elemToRunElems ns element
        let font = do
                     fontElem <- findElement (qualName "rFonts") element
                     stringToFont =<<
-                      foldr (<|>) Nothing (
-                        map (flip findAttr fontElem . qualName) ["ascii", "hAnsi"])
+                       foldr ((<|>) . (flip findAttr fontElem . qualName)) Nothing ["ascii", "hAnsi"]
        local (setFont font) (mapD (elemToRunElem ns) (elChildren element))
 elemToRunElems _ _ = throwError WrongElem
 
diff --git a/src/Text/Pandoc/Readers/HTML.hs b/src/Text/Pandoc/Readers/HTML.hs
index f15bf1c96..0e79f9ec3 100644
--- a/src/Text/Pandoc/Readers/HTML.hs
+++ b/src/Text/Pandoc/Readers/HTML.hs
@@ -43,14 +43,14 @@ module Text.Pandoc.Readers.HTML ( readHtml
                                 ) where
 
 import Control.Applicative ((<|>))
-import Control.Arrow ((***))
+import Control.Arrow (first)
 import Control.Monad (guard, mplus, msum, mzero, unless, void)
 import Control.Monad.Except (throwError)
 import Control.Monad.Reader (ReaderT, ask, asks, lift, local, runReaderT)
 import Data.Char (isAlphaNum, isDigit, isLetter)
 import Data.Default (Default (..), def)
 import Data.Foldable (for_)
-import Data.List (intercalate, isPrefixOf)
+import Data.List (isPrefixOf)
 import Data.List.Split (wordsBy, splitWhen)
 import qualified Data.Map as M
 import Data.Maybe (fromMaybe, isJust, isNothing)
@@ -777,7 +777,7 @@ pCode = try $ do
   (TagOpen open attr') <- pSatisfy $ tagOpen (`elem` ["code","tt"]) (const True)
   let attr = toStringAttr attr'
   result <- manyTill pAnyTag (pCloses open)
-  return $ B.codeWith (mkAttr attr) $ intercalate " " $ lines $ T.unpack $
+  return $ B.codeWith (mkAttr attr) $ unwords $ lines $ T.unpack $
            innerText result
 
 pSpan :: PandocMonad m => TagParser m Inlines
@@ -1227,7 +1227,7 @@ stripPrefixes = map stripPrefix
 
 stripPrefix :: Tag Text -> Tag Text
 stripPrefix (TagOpen s as) =
-    TagOpen (stripPrefix' s) (map (stripPrefix' *** id) as)
+    TagOpen (stripPrefix' s) (map (first stripPrefix') as)
 stripPrefix (TagClose s) = TagClose (stripPrefix' s)
 stripPrefix x = x
 
diff --git a/src/Text/Pandoc/Readers/JATS.hs b/src/Text/Pandoc/Readers/JATS.hs
index 9223db68c..8158a4511 100644
--- a/src/Text/Pandoc/Readers/JATS.hs
+++ b/src/Text/Pandoc/Readers/JATS.hs
@@ -494,4 +494,3 @@ parseInline (Elem e) =
                                "" -> []
                                l  -> [l]
            return $ codeWith (attrValue "id" e,classes',[]) $ strContentRecursive e
-
diff --git a/src/Text/Pandoc/Readers/LaTeX.hs b/src/Text/Pandoc/Readers/LaTeX.hs
index 3408201eb..1ce3d18e5 100644
--- a/src/Text/Pandoc/Readers/LaTeX.hs
+++ b/src/Text/Pandoc/Readers/LaTeX.hs
@@ -272,7 +272,7 @@ rawLaTeXBlock = do
   lookAhead (try (char '\\' >> letter))
   -- we don't want to apply newly defined latex macros to their own
   -- definitions:
-  (snd <$> rawLaTeXParser macroDef)
+  snd <$> rawLaTeXParser macroDef
   <|> ((snd <$> rawLaTeXParser (environment <|> blockCommand)) >>= applyMacros)
 
 rawLaTeXInline :: (PandocMonad m, HasMacros s, HasReaderOptions s)
@@ -351,7 +351,7 @@ totoks pos t =
                        Tok pos (Arg i) ("#" <> t1)
                        : totoks (incSourceColumn pos (1 + T.length t1)) t2
                     Nothing ->
-                       Tok pos Symbol ("#")
+                       Tok pos Symbol "#"
                        : totoks (incSourceColumn pos 1) t2
          | c == '^' ->
            case T.uncons rest of
@@ -369,10 +369,10 @@ totoks pos t =
                          | d < '\128' ->
                                   Tok pos Esc1 (T.pack ['^','^',d])
                                   : totoks (incSourceColumn pos 3) rest''
-                       _ -> Tok pos Symbol ("^") :
-                            Tok (incSourceColumn pos 1) Symbol ("^") :
+                       _ -> Tok pos Symbol "^" :
+                            Tok (incSourceColumn pos 1) Symbol "^" :
                             totoks (incSourceColumn pos 2) rest'
-                _ -> Tok pos Symbol ("^")
+                _ -> Tok pos Symbol "^"
                      : totoks (incSourceColumn pos 1) rest
          | otherwise ->
            Tok pos Symbol (T.singleton c) : totoks (incSourceColumn pos 1) rest
@@ -454,7 +454,7 @@ doMacros n = do
                            addTok _ (Tok _ (CtrlSeq x) txt)
                                   acc@(Tok _ Word _ : _)
                              | not (T.null txt) &&
-                               (isLetter (T.last txt)) =
+                               isLetter (T.last txt) =
                                Tok spos (CtrlSeq x) (txt <> " ") : acc
                            addTok _ t acc = setpos spos t : acc
                        ts' <- getInput
@@ -1244,7 +1244,7 @@ inlineEnvironments = M.fromList [
   ]
 
 inlineCommands :: PandocMonad m => M.Map Text (LP m Inlines)
-inlineCommands = M.union inlineLanguageCommands $ M.fromList $
+inlineCommands = M.union inlineLanguageCommands $ M.fromList
   [ ("emph", extractSpaces emph <$> tok)
   , ("textit", extractSpaces emph <$> tok)
   , ("textsl", extractSpaces emph <$> tok)
@@ -1501,7 +1501,7 @@ foreignlanguage :: PandocMonad m => LP m Inlines
 foreignlanguage = do
   babelLang <- T.unpack . untokenize <$> braced
   case babelLangToBCP47 babelLang of
-       Just lang -> spanWith ("", [], [("lang", renderLang $ lang)]) <$> tok
+       Just lang -> spanWith ("", [], [("lang",  renderLang lang)]) <$> tok
        _ -> tok
 
 inlineLanguageCommands :: PandocMonad m => M.Map Text (LP m Inlines)
@@ -2021,7 +2021,7 @@ closing = do
   return $ para (trimInlines contents) <> sigs
 
 blockCommands :: PandocMonad m => M.Map Text (LP m Blocks)
-blockCommands = M.fromList $
+blockCommands = M.fromList
    [ ("par", mempty <$ skipopts)
    , ("parbox",  skipopts >> braced >> grouped blocks)
    , ("title", mempty <$ (skipopts *>
@@ -2444,7 +2444,7 @@ parseAligns = try $ do
         spaces
         spec <- braced
         case safeRead ds of
-             Just n  -> do
+             Just n  ->
                getInput >>= setInput . (mconcat (replicate n spec) ++)
              Nothing -> fail $ "Could not parse " ++ ds ++ " as number"
   bgroup
diff --git a/src/Text/Pandoc/Readers/Markdown.hs b/src/Text/Pandoc/Readers/Markdown.hs
index 94f04eee7..92e9098bd 100644
--- a/src/Text/Pandoc/Readers/Markdown.hs
+++ b/src/Text/Pandoc/Readers/Markdown.hs
@@ -36,7 +36,7 @@ import Control.Monad
 import Control.Monad.Except (throwError)
 import Data.Char (isAlphaNum, isPunctuation, isSpace, toLower)
 import qualified Data.HashMap.Strict as H
-import Data.List (findIndex, intercalate, sortBy, transpose)
+import Data.List (intercalate, sortBy, transpose, elemIndex)
 import qualified Data.Map as M
 import Data.Maybe
 import Data.Monoid ((<>))
@@ -162,16 +162,14 @@ inlinesInBalancedBrackets =
         stripBracket xs = if last xs == ']' then init xs else xs
         go :: PandocMonad m => Int -> MarkdownParser m ()
         go 0 = return ()
-        go openBrackets = do
+        go openBrackets = 
           (() <$ (escapedChar <|>
-                  code <|>
-                  rawHtmlInline <|>
-                  rawLaTeXInline') >> go openBrackets)
+                code <|>
+                rawHtmlInline <|>
+                rawLaTeXInline') >> go openBrackets)
           <|>
           (do char ']'
-              if openBrackets > 1
-                 then go (openBrackets - 1)
-                 else return ())
+              Control.Monad.when (openBrackets > 1) $ go (openBrackets - 1))
           <|>
           (char '[' >> go (openBrackets + 1))
           <|>
@@ -257,13 +255,13 @@ yamlMetaBlock = try $ do
                   v' <- yamlToMeta v
                   let k' = T.unpack k
                   updateState $ \st -> st{ stateMeta' =
-                     (do m <- stateMeta' st
-                         -- if there's already a value, leave it unchanged
-                         case lookupMeta k' m of
-                              Just _ -> return m
-                              Nothing -> do
-                                v'' <- v'
-                                return $ B.setMeta (T.unpack k) v'' m)}
+                     do m <- stateMeta' st
+                        -- if there's already a value, leave it unchanged
+                        case lookupMeta k' m of
+                             Just _ -> return m
+                             Nothing -> do
+                               v'' <- v'
+                               return $ B.setMeta (T.unpack k) v'' m}
            ) alist
        Right Yaml.Null -> return ()
        Right _ -> do
@@ -596,7 +594,7 @@ setextHeader = try $ do
   underlineChar <- oneOf setextHChars
   many (char underlineChar)
   blanklines
-  let level = fromMaybe 0 (findIndex (== underlineChar) setextHChars) + 1
+  let level = fromMaybe 0 (elemIndex underlineChar setextHChars) + 1
   attr' <- registerHeader attr (runF text defaultParserState)
   guardDisabled Ext_implicit_header_references
     <|> registerImplicitHeader raw attr'
@@ -851,7 +849,7 @@ orderedListStart mbstydelim = try $ do
        return (num, style, delim))
 
 listStart :: PandocMonad m => MarkdownParser m ()
-listStart = bulletListStart <|> (Control.Monad.void (orderedListStart Nothing))
+listStart = bulletListStart <|> Control.Monad.void (orderedListStart Nothing)
 
 listLine :: PandocMonad m => Int -> MarkdownParser m String
 listLine continuationIndent = try $ do
@@ -881,7 +879,7 @@ rawListItem fourSpaceRule start = try $ do
   pos2 <- getPosition
   let continuationIndent = if fourSpaceRule
                               then 4
-                              else (sourceColumn pos2 - sourceColumn pos1)
+                              else sourceColumn pos2 - sourceColumn pos1
   first <- listLineCommon
   rest <- many (do notFollowedBy listStart
                    notFollowedBy (() <$ codeBlockFenced)
@@ -912,10 +910,10 @@ listContinuation continuationIndent = try $ do
   return $ concat (x:xs) ++ blanks
 
 notFollowedByDivCloser :: PandocMonad m => MarkdownParser m ()
-notFollowedByDivCloser = do
+notFollowedByDivCloser =
   guardDisabled Ext_fenced_divs <|>
-    do divLevel <- stateFencedDivLevel <$> getState
-       guard (divLevel < 1) <|> notFollowedBy divFenceEnd
+  do divLevel <- stateFencedDivLevel <$> getState
+     guard (divLevel < 1) <|> notFollowedBy divFenceEnd
 
 notFollowedByHtmlCloser :: PandocMonad m => MarkdownParser m ()
 notFollowedByHtmlCloser = do
@@ -1222,7 +1220,7 @@ simpleTableHeader headless = try $ do
               if headless
                  then lookAhead anyLine
                  else return rawContent
-  let aligns   = zipWith alignType (map ((: [])) rawHeads) lengths
+  let aligns   = zipWith alignType (map (: []) rawHeads) lengths
   let rawHeads' = if headless
                      then replicate (length dashes) ""
                      else rawHeads
@@ -1418,11 +1416,11 @@ pipeTableHeaderPart = try $ do
   skipMany spaceChar
   let len = length pipe + maybe 0 (const 1) left + maybe 0 (const 1) right
   return
-    ((case (left,right) of
-       (Nothing,Nothing) -> AlignDefault
-       (Just _,Nothing)  -> AlignLeft
-       (Nothing,Just _)  -> AlignRight
-       (Just _,Just _)   -> AlignCenter), len)
+    (case (left,right) of
+      (Nothing,Nothing) -> AlignDefault
+      (Just _,Nothing)  -> AlignLeft
+      (Nothing,Just _)  -> AlignRight
+      (Just _,Just _)   -> AlignCenter, len)
 
 -- Succeed only if current line contains a pipe.
 scanForPipe :: PandocMonad m => ParserT [Char] st m ()
@@ -1929,7 +1927,7 @@ rawConTeXtEnvironment = try $ do
                        (try $ string "\\stop" >> string completion)
   return $ "\\start" ++ completion ++ concat contents ++ "\\stop" ++ completion
 
-inBrackets :: PandocMonad m => (ParserT [Char] st m Char) -> ParserT [Char] st m String
+inBrackets :: PandocMonad m => ParserT [Char] st m Char -> ParserT [Char] st m String
 inBrackets parser = do
   char '['
   contents <- many parser
@@ -2150,6 +2148,6 @@ doubleQuoted :: PandocMonad m => MarkdownParser m (F Inlines)
 doubleQuoted = try $ do
   doubleQuoteStart
   contents <- mconcat <$> many (try $ notFollowedBy doubleQuoteEnd >> inline)
-  (withQuoteContext InDoubleQuote $ doubleQuoteEnd >> return
+  withQuoteContext InDoubleQuote (doubleQuoteEnd >> return
        (fmap B.doubleQuoted . trimInlinesF $ contents))
-   <|> (return $ return (B.str "\8220") <> contents)
+   <|> return (return (B.str "\8220") <> contents)
diff --git a/src/Text/Pandoc/Readers/Muse.hs b/src/Text/Pandoc/Readers/Muse.hs
index 4c6d1278e..973dfa15c 100644
--- a/src/Text/Pandoc/Readers/Muse.hs
+++ b/src/Text/Pandoc/Readers/Muse.hs
@@ -482,7 +482,7 @@ definitionList :: PandocMonad m => MuseParser m (F Blocks)
 definitionList = try $ do
   many spaceChar
   pos <- getPosition
-  (guardDisabled Ext_amuse) <|> (guard (sourceColumn pos /= 1)) -- Initial space is required by Amusewiki, but not Emacs Muse
+  guardDisabled Ext_amuse <|> guard (sourceColumn pos /= 1) -- Initial space is required by Amusewiki, but not Emacs Muse
   first <- definitionListItem 0
   rest <- many $ try (optionMaybe blankline >> definitionListItem (sourceColumn pos - 1))
   return $ B.definitionList <$> sequence (first : rest)
diff --git a/src/Text/Pandoc/Readers/Odt/Arrows/Utils.hs b/src/Text/Pandoc/Readers/Odt/Arrows/Utils.hs
index cdfa8f8df..ef8b2d18a 100644
--- a/src/Text/Pandoc/Readers/Odt/Arrows/Utils.hs
+++ b/src/Text/Pandoc/Readers/Odt/Arrows/Utils.hs
@@ -211,9 +211,9 @@ a ^>>?% f = arr a >>?^ (uncurry f)
 ---
 (>>?%?) :: (ArrowChoice a)
            => FallibleArrow a x f (b,b')
-           -> (b -> b' -> (Either f c))
+           -> (b -> b' -> Either f c)
            -> FallibleArrow a x f c
-a >>?%? f = a >>?^? (uncurry f)
+a >>?%? f = a >>?^? uncurry f
 
 infixr 1  >>?,  >>?^,  >>?^?
 infixr 1 ^>>?, >>?!
diff --git a/src/Text/Pandoc/Readers/Odt/ContentReader.hs b/src/Text/Pandoc/Readers/Odt/ContentReader.hs
index cc9b798b3..380f16c66 100644
--- a/src/Text/Pandoc/Readers/Odt/ContentReader.hs
+++ b/src/Text/Pandoc/Readers/Odt/ContentReader.hs
@@ -322,7 +322,7 @@ type InlineModifier = Inlines -> Inlines
 modifierFromStyleDiff :: PropertyTriple -> InlineModifier
 modifierFromStyleDiff propertyTriple  =
   composition $
-  (getVPosModifier propertyTriple)
+  getVPosModifier propertyTriple
   : map (first ($ propertyTriple) >>> ifThen_else ignore)
         [ (hasEmphChanged           , emph      )
         , (hasChanged isStrong      , strong    )
@@ -352,7 +352,7 @@ modifierFromStyleDiff propertyTriple  =
                                ]
 
     hasChanged property triple@(_, property -> newProperty, _) =
-        maybe True (/=newProperty) (lookupPreviousValue property triple)
+        (/= Just newProperty) (lookupPreviousValue property triple)
 
     hasChangedM property triple@(_, textProps,_) =
       fromMaybe False $ (/=) <$> property textProps <*> lookupPreviousValueM property triple
@@ -362,7 +362,7 @@ modifierFromStyleDiff propertyTriple  =
     lookupPreviousValueM f = lookupPreviousStyleValue ((f =<<).textProperties)
 
     lookupPreviousStyleValue f (ReaderState{..},_,mFamily)
-      =     ( findBy f $ extendedStylePropertyChain styleTrace styleSet )
+      =     findBy f (extendedStylePropertyChain styleTrace styleSet)
         <|> ( f =<< fmap (lookupDefaultStyle' styleSet) mFamily         )
 
 
@@ -793,8 +793,7 @@ read_image_src = matchingElement NsDraw "image"
                       Left _    -> returnV ""  -< ()
 
 read_frame_title :: InlineMatcher
-read_frame_title = matchingElement NsSVG "title"
-                   $ (matchChildContent [] read_plain_text)
+read_frame_title = matchingElement NsSVG "title" (matchChildContent [] read_plain_text)
 
 read_frame_text_box :: InlineMatcher
 read_frame_text_box = matchingElement NsDraw "text-box"
@@ -803,12 +802,12 @@ read_frame_text_box = matchingElement NsDraw "text-box"
                          arr read_img_with_caption                             -< toList paragraphs
 
 read_img_with_caption :: [Block] -> Inlines
-read_img_with_caption ((Para [Image attr alt (src,title)]) : _) =
+read_img_with_caption (Para [Image attr alt (src,title)] : _) =
   singleton (Image attr alt (src, 'f':'i':'g':':':title))   -- no text, default caption
 read_img_with_caption (Para (Image attr _ (src,title) : txt) : _) =
   singleton (Image attr txt (src, 'f':'i':'g':':':title) )  -- override caption with the text that follows
-read_img_with_caption  ( (Para (_ : xs)) : ys) =
-  read_img_with_caption ((Para xs) : ys)
+read_img_with_caption  ( Para (_ : xs) : ys) =
+  read_img_with_caption (Para xs : ys)
 read_img_with_caption _ =
   mempty
 
@@ -909,8 +908,8 @@ post_process (Pandoc m blocks) =
   Pandoc m (post_process' blocks)
 
 post_process' :: [Block] -> [Block]
-post_process' ((Table _ a w h r) : (Div ("", ["caption"], _) [Para inlines] ) : xs) =
-  (Table inlines a w h r) : ( post_process' xs )
+post_process' (Table _ a w h r : Div ("", ["caption"], _) [Para inlines] : xs) =
+  Table inlines a w h r : post_process' xs
 post_process' bs = bs
 
 read_body :: OdtReader _x (Pandoc, MediaBag)
diff --git a/src/Text/Pandoc/Readers/Odt/Namespaces.hs b/src/Text/Pandoc/Readers/Odt/Namespaces.hs
index 3c11aeb8e..92e12931d 100644
--- a/src/Text/Pandoc/Readers/Odt/Namespaces.hs
+++ b/src/Text/Pandoc/Readers/Odt/Namespaces.hs
@@ -48,7 +48,7 @@ instance NameSpaceID Namespace where
 
 
 findID :: NameSpaceIRI -> Maybe Namespace
-findID iri = listToMaybe [nsID | (iri',~nsID) <- nsIDs, iri' `isPrefixOf` iri]
+findID iri = listToMaybe [nsID | (iri',nsID) <- nsIDs, iri' `isPrefixOf` iri]
 
 nsIDmap :: NameSpaceIRIs Namespace
 nsIDmap = foldr (uncurry $ flip M.insert) M.empty nsIDs
diff --git a/src/Text/Pandoc/Readers/Odt/StyleReader.hs b/src/Text/Pandoc/Readers/Odt/StyleReader.hs
index 6129c1664..58be8e4a3 100644
--- a/src/Text/Pandoc/Readers/Odt/StyleReader.hs
+++ b/src/Text/Pandoc/Readers/Odt/StyleReader.hs
@@ -131,13 +131,12 @@ type StyleReaderSafe a b  = XMLReaderSafe FontPitches a b
 -- | A reader for font pitches
 fontPitchReader :: XMLReader _s _x FontPitches
 fontPitchReader = executeIn NsOffice "font-face-decls" (
-                         (  withEveryL NsStyle "font-face" $ liftAsSuccess (
+                          withEveryL NsStyle "font-face" (liftAsSuccess (
                               findAttr' NsStyle "name"
                               &&&
                               lookupDefaultingAttr NsStyle "font-pitch"
-                            )
-                         )
-                    >>?^ ( M.fromList . (foldl accumLegalPitches []) )
+                            ))
+                    >>?^ ( M.fromList . foldl accumLegalPitches [] )
                   )
   where accumLegalPitches ls (Nothing,_) = ls
         accumLegalPitches ls (Just n,p)  = (n,p):ls
@@ -383,11 +382,11 @@ data ListLevelStyle = ListLevelStyle { listLevelType  :: ListLevelType
 
 instance Show ListLevelStyle where
   show ListLevelStyle{..} =    "<LLS|"
-                            ++ (show listLevelType)
+                            ++ show listLevelType
                             ++ "|"
-                            ++ (maybeToString listItemPrefix)
-                            ++ (show listItemFormat)
-                            ++ (maybeToString listItemSuffix)
+                            ++ maybeToString listItemPrefix
+                            ++ show listItemFormat
+                            ++ maybeToString listItemSuffix
                             ++ ">"
     where maybeToString = fromMaybe ""
 
@@ -483,14 +482,14 @@ readTextProperties =
     ( liftA6 PropT
        ( searchAttr   NsXSL_FO "font-style"  False isFontEmphasised )
        ( searchAttr   NsXSL_FO "font-weight" False isFontBold       )
-       ( findPitch                                                  )
+       findPitch
        ( getAttr      NsStyle  "text-position"                      )
-       ( readUnderlineMode                                          )
-       ( readStrikeThroughMode                                      )
+       readUnderlineMode
+       readStrikeThroughMode
      )
   where isFontEmphasised = [("normal",False),("italic",True),("oblique",True)]
         isFontBold = ("normal",False):("bold",True)
-                    :(map ((,True).show) ([100,200..900]::[Int]))
+                    :map ((,True).show) ([100,200..900]::[Int])
 
 readUnderlineMode     :: StyleReaderSafe _x (Maybe UnderlineMode)
 readUnderlineMode     = readLineMode "text-underline-mode"
@@ -510,7 +509,7 @@ readLineMode modeAttr styleAttr = proc x -> do
            Nothing -> returnA -< Just UnderlineModeNormal
     else              returnA -< Nothing
   where
-    isLinePresent = [("none",False)] ++ map (,True)
+    isLinePresent = ("none",False) : map (,True)
                     [ "dash"      , "dot-dash" , "dot-dot-dash" , "dotted"
                     , "long-dash" , "solid"    , "wave"
                     ]
@@ -547,20 +546,18 @@ readListStyle =
        findAttr NsStyle "name"
   >>?! keepingTheValue
        ( liftA ListStyle
-         $ ( liftA3 SM.union3
+         $ liftA3 SM.union3
              ( readListLevelStyles NsText "list-level-style-number" LltNumbered )
              ( readListLevelStyles NsText "list-level-style-bullet" LltBullet   )
-             ( readListLevelStyles NsText "list-level-style-image"  LltImage    )
-           ) >>^ M.mapMaybe chooseMostSpecificListLevelStyle
+             ( readListLevelStyles NsText "list-level-style-image"  LltImage    ) >>^ M.mapMaybe chooseMostSpecificListLevelStyle
        )
 --
 readListLevelStyles :: Namespace -> ElementName
                     -> ListLevelType
                     -> StyleReaderSafe _x (SM.SetMap Int ListLevelStyle)
 readListLevelStyles namespace elementName levelType =
-  (     tryAll namespace elementName (readListLevelStyle levelType)
+  tryAll namespace elementName (readListLevelStyle levelType)
     >>^ SM.fromList
-  )
 
 --
 readListLevelStyle :: ListLevelType -> StyleReader _x (Int, ListLevelStyle)
@@ -632,7 +629,7 @@ parents style styles = unfoldr findNextParent style -- Ha!
 getStyleFamily        :: Style       -> Styles -> Maybe StyleFamily
 getStyleFamily style@Style{..} styles
   =     styleFamily
-    <|> (F.asum $ map (`getStyleFamily` styles) $ parents style styles)
+    <|> F.asum (map (`getStyleFamily` styles) $ parents style styles)
 
 -- | Each 'Style' has certain 'StyleProperties'. But sometimes not all property
 -- values are specified. Instead, a value might be inherited from a
@@ -654,7 +651,7 @@ stylePropertyChain style styles
 --
 extendedStylePropertyChain :: [Style] -> Styles -> [StyleProperties]
 extendedStylePropertyChain [] _ = []
-extendedStylePropertyChain [style]       styles =    (stylePropertyChain style styles)
-                                                  ++ (maybeToList (fmap (lookupDefaultStyle' styles) (getStyleFamily style styles)))
-extendedStylePropertyChain (style:trace) styles =    (stylePropertyChain style styles)
-                                                  ++ (extendedStylePropertyChain trace styles)
+extendedStylePropertyChain [style]       styles =    stylePropertyChain style styles
+                                                  ++ maybeToList (fmap (lookupDefaultStyle' styles) (getStyleFamily style styles))
+extendedStylePropertyChain (style:trace) styles =    stylePropertyChain style styles
+                                                  ++ extendedStylePropertyChain trace styles
diff --git a/src/Text/Pandoc/Readers/Org/Blocks.hs b/src/Text/Pandoc/Readers/Org/Blocks.hs
index c5a7d8e10..fa016283c 100644
--- a/src/Text/Pandoc/Readers/Org/Blocks.hs
+++ b/src/Text/Pandoc/Readers/Org/Blocks.hs
@@ -516,7 +516,7 @@ include = try $ do
   blocksParser <- case includeArgs of
       ("example" : _) -> return $ pure . B.codeBlock <$> parseRaw
       ["export"] -> return . returnF $ B.fromList []
-      ("export" : format : []) -> return $ pure . B.rawBlock format <$> parseRaw
+      ["export", format] -> return $ pure . B.rawBlock format <$> parseRaw
       ("src" : rest) -> do
         let attr = case rest of
                      [lang] -> (mempty, [lang], mempty)
diff --git a/src/Text/Pandoc/Readers/RST.hs b/src/Text/Pandoc/Readers/RST.hs
index 49cc3018c..0e90fe945 100644
--- a/src/Text/Pandoc/Readers/RST.hs
+++ b/src/Text/Pandoc/Readers/RST.hs
@@ -1263,7 +1263,7 @@ simpleTableHeader headless = try $ do
   let rawHeads = if headless
                     then replicate (length dashes) ""
                     else simpleTableSplitLine indices rawContent
-  heads <- mapM ( (parseFromString' (mconcat <$> many plain)) . trim) rawHeads
+  heads <- mapM ( parseFromString' (mconcat <$> many plain) . trim) rawHeads
   return (heads, aligns, indices)
 
 -- Parse a simple table.
@@ -1414,7 +1414,7 @@ renderRole contents fmt role attr = case role of
            pepUrl = "http://www.python.org/dev/peps/pep-" ++ padNo ++ "/"
 
 addClass :: String -> Attr -> Attr
-addClass c (ident, classes, keyValues) = (ident, union classes [c], keyValues)
+addClass c (ident, classes, keyValues) = (ident, classes `union` [c], keyValues)
 
 roleName :: PandocMonad m => RSTParser m String
 roleName = many1 (letter <|> char '-')
@@ -1454,7 +1454,7 @@ endline = try $ do
   notFollowedBy blankline
   -- parse potential list-starts at beginning of line differently in a list:
   st <- getState
-  when ((stateParserContext st) == ListItemState) $ notFollowedBy (anyOrderedListMarker >> spaceChar) >>
+  when (stateParserContext st == ListItemState) $ notFollowedBy (anyOrderedListMarker >> spaceChar) >>
           notFollowedBy' bulletListStart
   return B.softbreak
 
@@ -1577,7 +1577,7 @@ note = try $ do
       -- not yet in this implementation.
       updateState $ \st -> st{ stateNotes = [] }
       contents <- parseFromString' parseBlocks raw
-      let newnotes = if (ref == "*" || ref == "#") -- auto-numbered
+      let newnotes = if ref == "*" || ref == "#" -- auto-numbered
                         -- delete the note so the next auto-numbered note
                         -- doesn't get the same contents:
                         then deleteFirstsBy (==) notes [(ref,raw)]
diff --git a/src/Text/Pandoc/Readers/Textile.hs b/src/Text/Pandoc/Readers/Textile.hs
index 46d6301e4..30bb6a715 100644
--- a/src/Text/Pandoc/Readers/Textile.hs
+++ b/src/Text/Pandoc/Readers/Textile.hs
@@ -110,7 +110,7 @@ noteBlock = try $ do
   startPos <- getPosition
   ref <- noteMarker
   optional blankline
-  contents <- fmap unlines $ many1Till anyLine (blanklines <|> noteBlock)
+  contents <- unlines <$> many1Till anyLine (blanklines <|> noteBlock)
   endPos <- getPosition
   let newnote = (ref, contents ++ "\n")
   st <- getState
@@ -360,7 +360,7 @@ cellAttributes = try $ do
 tableCell :: PandocMonad m => ParserT [Char] ParserState m ((Bool, Alignment), Blocks)
 tableCell = try $ do
   char '|'
-  (isHeader, alignment) <- option (False, AlignDefault) $ cellAttributes
+  (isHeader, alignment) <- option (False, AlignDefault) cellAttributes
   notFollowedBy blankline
   raw <- trim <$>
          many (noneOf "|\n" <|> try (char '\n' <* notFollowedBy blankline))
@@ -499,7 +499,7 @@ copy = do
 
 note :: PandocMonad m => ParserT [Char] ParserState m Inlines
 note = try $ do
-  ref <- (char '[' *> many1 digit <* char ']')
+  ref <- char '[' *> many1 digit <* char ']'
   notes <- stateNotes <$> getState
   case lookup ref notes of
     Nothing  -> fail "note not found"
@@ -530,7 +530,7 @@ hyphenedWords = do
 wordChunk :: PandocMonad m => ParserT [Char] ParserState m String
 wordChunk = try $ do
   hd <- noneOf wordBoundaries
-  tl <- many ( (noneOf wordBoundaries) <|>
+  tl <- many ( noneOf wordBoundaries <|>
                try (notFollowedBy' note *> oneOf markupChars
                      <* lookAhead (noneOf wordBoundaries) ) )
   return $ hd:tl
@@ -614,7 +614,7 @@ escapedEqs = B.str <$>
 -- | literal text escaped btw <notextile> tags
 escapedTag :: PandocMonad m => ParserT [Char] ParserState m Inlines
 escapedTag = B.str <$>
-  (try $ string "<notextile>" *>
+  try (string "<notextile>" *>
          manyTill anyChar' (try $ string "</notextile>"))
 
 -- | Any special symbol defined in wordBoundaries
@@ -630,7 +630,8 @@ code = code1 <|> code2
 -- any character except a newline before a blank line
 anyChar' :: PandocMonad m => ParserT [Char] ParserState m Char
 anyChar' =
-  satisfy (/='\n') <|> (try $ char '\n' <* notFollowedBy blankline)
+  satisfy (/='\n') <|>
+  try (char '\n' <* notFollowedBy blankline)
 
 code1 :: PandocMonad m => ParserT [Char] ParserState m Inlines
 code1 = B.code <$> surrounded (char '@') anyChar'
diff --git a/src/Text/Pandoc/Readers/TikiWiki.hs b/src/Text/Pandoc/Readers/TikiWiki.hs
index 4a66cc13d..a92f7bed2 100644
--- a/src/Text/Pandoc/Readers/TikiWiki.hs
+++ b/src/Text/Pandoc/Readers/TikiWiki.hs
@@ -168,7 +168,7 @@ table = try $ do
   where
     -- The headers are as many empty srings as the number of columns
     -- in the first row
-    headers rows = map (B.plain . B.str) $replicate (length $ rows !! 0) ""
+    headers rows = map (B.plain . B.str) $replicate (length $ head rows) ""
 
 para :: PandocMonad m => TikiWikiParser m B.Blocks
 para =  fmap (result . mconcat) ( many1Till inline endOfParaElement)
@@ -238,8 +238,8 @@ fixListNesting [first] = [recurseOnList first]
 fixListNesting (first:second:rest) =
   let secondBlock = head $ B.toList second in
     case secondBlock of
-      BulletList _ -> fixListNesting $ (mappend (recurseOnList first) (recurseOnList second)) : rest
-      OrderedList _ _ -> fixListNesting $ (mappend (recurseOnList first) (recurseOnList second)) : rest
+      BulletList _ -> fixListNesting $ mappend (recurseOnList first) (recurseOnList second) : rest
+      OrderedList _ _ -> fixListNesting $ mappend (recurseOnList first) (recurseOnList second) : rest
       _ -> recurseOnList first : fixListNesting (second:rest)
 
 -- This function walks the Block structure for fixListNesting,
@@ -285,7 +285,7 @@ spanFoldUpList ln (first:rest) =
 -- level and of the same type.
 splitListNesting :: ListNesting -> (ListNesting, B.Blocks) -> Bool
 splitListNesting ln1 (ln2, _)
-  | (lnnest ln1) < (lnnest ln2) =
+  | lnnest ln1 < lnnest ln2 =
   True
   | ln1 == ln2 =
   True
@@ -341,7 +341,7 @@ listItemLine nest = lineContent >>= parseContent
     lineContent = do
       content <- anyLine
       continuation <- optionMaybe listContinuation
-      return $ filterSpaces content ++ "\n" ++ maybe "" id continuation
+      return $ filterSpaces content ++ "\n" ++ Data.Maybe.fromMaybe "" continuation
     filterSpaces = reverse . dropWhile (== ' ') . reverse
     listContinuation = string (replicate nest '+') >> lineContent
     parseContent x = do
@@ -410,7 +410,7 @@ inline = choice [ whitespace
                 ] <?> "inline"
 
 whitespace :: PandocMonad m => TikiWikiParser m B.Inlines
-whitespace = (lb <|> regsp)
+whitespace = lb <|> regsp
   where lb = try $ skipMany spaceChar >> linebreak >> return B.space
         regsp = try $ skipMany1 spaceChar >> return B.space
 
@@ -501,7 +501,7 @@ escapedChar = try $ do
   string "~"
   inner <- many1 $ oneOf "0123456789"
   string "~"
-  return $B.str [(toEnum (read inner :: Int)) :: Char]
+  return $B.str [toEnum (read inner :: Int) :: Char]
 
 -- UNSUPPORTED, as there doesn't seem to be any facility in calibre
 -- for this
diff --git a/src/Text/Pandoc/Readers/Txt2Tags.hs b/src/Text/Pandoc/Readers/Txt2Tags.hs
index 68399afc9..b4f4bc564 100644
--- a/src/Text/Pandoc/Readers/Txt2Tags.hs
+++ b/src/Text/Pandoc/Readers/Txt2Tags.hs
@@ -36,7 +36,7 @@ import Control.Monad.Except (catchError, throwError)
 import Control.Monad.Reader (Reader, asks, runReader)
 import Data.Char (toLower)
 import Data.Default
-import Data.List (intercalate, intersperse, transpose)
+import Data.List (intercalate, transpose)
 import Data.Maybe (fromMaybe)
 import Data.Monoid ((<>))
 import Data.Text (Text)
@@ -463,7 +463,7 @@ titleLink = try $ do
   char ']'
   let link' = last tokens
   guard $ not $ null link'
-  let tit = concat (intersperse " " (init tokens))
+  let tit = unwords (init tokens)
   return $ B.link link' "" (B.text tit)
 
 -- Link with image
diff --git a/src/Text/Pandoc/Readers/Vimwiki.hs b/src/Text/Pandoc/Readers/Vimwiki.hs
index 162fb371e..d717a1ba8 100644
--- a/src/Text/Pandoc/Readers/Vimwiki.hs
+++ b/src/Text/Pandoc/Readers/Vimwiki.hs
@@ -388,9 +388,7 @@ bulletListMarkers = "ul" <$ (char '*' <|> char '-')
 
 orderedListMarkers :: PandocMonad m => VwParser m String
 orderedListMarkers =
-  ("ol" <$choice (orderedListMarker Decimal Period:(($OneParen)
-    <$> orderedListMarker
-    <$> [Decimal, LowerRoman, UpperRoman, LowerAlpha, UpperAlpha])))
+  ("ol" <$choice (orderedListMarker Decimal Period:(($OneParen) . orderedListMarker <$> [Decimal, LowerRoman, UpperRoman, LowerAlpha, UpperAlpha])))
     <|> ("ol" <$ char '#')
 
 --many need trimInlines
diff --git a/src/Text/Pandoc/Shared.hs b/src/Text/Pandoc/Shared.hs
index 583c7a63f..52e1447db 100644
--- a/src/Text/Pandoc/Shared.hs
+++ b/src/Text/Pandoc/Shared.hs
@@ -494,7 +494,7 @@ hierarchicalizeWithIds (Header level attr@(_,classes,_) title':xs) = do
   return $ Sec level newnum attr title' sectionContents' : rest'
 hierarchicalizeWithIds (Div ("",["references"],[])
                          (Header level (ident,classes,kvs) title' : xs):ys) =
-  hierarchicalizeWithIds (Header level (ident,("references":classes),kvs)
+  hierarchicalizeWithIds (Header level (ident,"references":classes,kvs)
                            title' : (xs ++ ys))
 hierarchicalizeWithIds (x:rest) = do
   rest' <- hierarchicalizeWithIds rest
diff --git a/src/Text/Pandoc/Writers/AsciiDoc.hs b/src/Text/Pandoc/Writers/AsciiDoc.hs
index a6906eb68..b8f647b66 100644
--- a/src/Text/Pandoc/Writers/AsciiDoc.hs
+++ b/src/Text/Pandoc/Writers/AsciiDoc.hs
@@ -265,8 +265,7 @@ blockToAsciiDoc opts (OrderedList (_start, sty, _delim) items) = do
   let markers' = map (\m -> if length m < 3
                                then m ++ replicate (3 - length m) ' '
                                else m) markers
-  contents <- mapM (uncurry (orderedListItemToAsciiDoc opts)) $
-              zip markers' items
+  contents <- zipWithM (orderedListItemToAsciiDoc opts) markers' items
   return $ cat contents <> blankline
 blockToAsciiDoc opts (DefinitionList items) = do
   contents <- mapM (definitionListItemToAsciiDoc opts) items
@@ -452,7 +451,7 @@ inlineToAsciiDoc opts (Link _ txt (src, _tit)) = do
               else prefix <> text src <> "[" <> linktext <> "]"
 inlineToAsciiDoc opts (Image attr alternate (src, tit)) = do
 -- image:images/logo.png[Company logo, title="blah"]
-  let txt = if (null alternate) || (alternate == [Str ""])
+  let txt = if null alternate || (alternate == [Str ""])
                then [Str "image"]
                else alternate
   linktext <- inlineListToAsciiDoc opts txt
diff --git a/src/Text/Pandoc/Writers/Docx.hs b/src/Text/Pandoc/Writers/Docx.hs
index adf5f232a..928eaa712 100644
--- a/src/Text/Pandoc/Writers/Docx.hs
+++ b/src/Text/Pandoc/Writers/Docx.hs
@@ -1057,12 +1057,9 @@ getParaProps displayMathPara = do
   props <- asks envParaProperties
   listLevel <- asks envListLevel
   numid <- asks envListNumId
-  let listPr = if listLevel >= 0 && not displayMathPara
-                  then [ mknode "w:numPr" []
-                         [ mknode "w:numId" [("w:val",show numid)] ()
-                         , mknode "w:ilvl" [("w:val",show listLevel)] () ]
-                       ]
-                  else []
+  let listPr = [mknode "w:numPr" []
+                [ mknode "w:numId" [("w:val",show numid)] ()
+                , mknode "w:ilvl" [("w:val",show listLevel)] () ] | listLevel >= 0 && not displayMathPara]
   return $ case props ++ listPr of
                 [] -> []
                 ps -> [mknode "w:pPr" [] ps]
@@ -1145,7 +1142,7 @@ inlineToOpenXML' opts (Span (ident,classes,kvs) ils) = do
                  return $ \f -> do
                    x <- f
                    return [ mknode "w:ins"
-                              [("w:id", (show insId)),
+                              [("w:id", show insId),
                               ("w:author", author),
                               ("w:date", date)] x ]
                else return id
@@ -1272,7 +1269,7 @@ inlineToOpenXML' opts (Image attr alt (src, title)) = do
     Nothing ->
       catchError
       (do (img, mt) <- P.fetchItem src
-          ident <- ("rId"++) `fmap` ((lift . lift) getUniqueId)
+          ident <- ("rId"++) `fmap` (lift . lift) getUniqueId
           let (xpt,ypt) = desiredSizeInPoints opts attr
                  (either (const def) id (imageSize opts img))
           -- 12700 emu = 1 pt
diff --git a/src/Text/Pandoc/Writers/FB2.hs b/src/Text/Pandoc/Writers/FB2.hs
index b1e8c8575..e322c7d98 100644
--- a/src/Text/Pandoc/Writers/FB2.hs
+++ b/src/Text/Pandoc/Writers/FB2.hs
@@ -131,8 +131,7 @@ description meta' = do
                     _       -> return []
   return $ el "description"
     [ el "title-info" (genre : (bt ++ as ++ dd ++ lang))
-    , el "document-info" ([ el "program-used" "pandoc" ] -- FIXME: +version
-                          ++ coverpage)
+    , el "document-info" (el "program-used" "pandoc" : coverpage)
     ]
 
 booktitle :: PandocMonad m => Meta -> FBM m [Content]
diff --git a/src/Text/Pandoc/Writers/HTML.hs b/src/Text/Pandoc/Writers/HTML.hs
index 5d5c88dd9..9e2347798 100644
--- a/src/Text/Pandoc/Writers/HTML.hs
+++ b/src/Text/Pandoc/Writers/HTML.hs
@@ -56,7 +56,8 @@ import qualified Data.Text.Lazy as TL
 import Network.HTTP (urlEncode)
 import Network.URI (URI (..), parseURIReference, unEscapeString)
 import Numeric (showHex)
-import Text.Blaze.Internal (customLeaf, MarkupM(Empty))
+import Text.Blaze.Internal
+       (customLeaf, MarkupM(Empty), preEscapedString, preEscapedText)
 import Text.Blaze.Html hiding (contents)
 import Text.Pandoc.Definition
 import Text.Pandoc.Highlighting (formatHtmlBlock, formatHtmlInline, highlight,
@@ -424,7 +425,7 @@ elementToHtml slideLevel opts (Sec level num (id',classes,keyvals) title' elemen
                   modify (\st -> st{ stElement = False})
                   return res
 
-  let isSec (Sec{}) = True
+  let isSec Sec{} = True
       isSec (Blk _) = False
   let isPause (Blk x) = x == Para [Str ".",Space,Str ".",Space,Str "."]
       isPause _       = False
@@ -618,7 +619,7 @@ imageExts = [ "art", "bmp", "cdr", "cdt", "cpt", "cr2", "crw", "djvu", "erf",
 
 treatAsImage :: FilePath -> Bool
 treatAsImage fp =
-  let path = fromMaybe fp (uriPath `fmap` parseURIReference fp)
+  let path = maybe fp uriPath (parseURIReference fp)
       ext  = map toLower $ drop 1 $ takeExtension path
   in  null ext || ext `elem` imageExts
 
@@ -797,8 +798,8 @@ blockToHtml opts (OrderedList (startnum, numstyle, _) lst) = do
   let numstyle' = case numstyle of
                        Example -> "decimal"
                        _       -> camelCaseToHyphenated $ show numstyle
-  let attribs = ([A.start $ toValue startnum | startnum /= 1]) ++
-                ([A.class_ "example" | numstyle == Example]) ++
+  let attribs = [A.start $ toValue startnum | startnum /= 1] ++
+                [A.class_ "example" | numstyle == Example] ++
                 (if numstyle /= DefaultStyle
                    then if html5
                            then [A.type_ $
@@ -819,7 +820,7 @@ blockToHtml opts (DefinitionList lst) = do
                   do term' <- if null term
                                  then return mempty
                                  else liftM H.dt $ inlineListToHtml opts term
-                     defs' <- mapM (liftM (\x -> H.dd $ (x >> nl opts)) .
+                     defs' <- mapM (liftM (\x -> H.dd (x >> nl opts)) .
                                     blockListToHtml opts) defs
                      return $ mconcat $ nl opts : term' : nl opts :
                                         intersperse (nl opts) defs') lst
diff --git a/src/Text/Pandoc/Writers/Haddock.hs b/src/Text/Pandoc/Writers/Haddock.hs
index 9ed3be6cf..688c1f390 100644
--- a/src/Text/Pandoc/Writers/Haddock.hs
+++ b/src/Text/Pandoc/Writers/Haddock.hs
@@ -168,8 +168,7 @@ blockToHaddock opts (OrderedList (start,_,delim) items) = do
   let markers' = map (\m -> if length m < 3
                                then m ++ replicate (3 - length m) ' '
                                else m) markers
-  contents <- mapM (uncurry (orderedListItemToHaddock opts)) $
-              zip markers' items
+  contents <- zipWithM (orderedListItemToHaddock opts) markers' items
   return $ cat contents <> blankline
 blockToHaddock opts (DefinitionList items) = do
   contents <- mapM (definitionListItemToHaddock opts) items
diff --git a/src/Text/Pandoc/Writers/ICML.hs b/src/Text/Pandoc/Writers/ICML.hs
index 80d2fcbef..a5d851e40 100644
--- a/src/Text/Pandoc/Writers/ICML.hs
+++ b/src/Text/Pandoc/Writers/ICML.hs
@@ -154,7 +154,7 @@ writeICML opts (Pandoc meta blocks) = do
 -- | Auxilary functions for parStylesToDoc and charStylesToDoc.
 contains :: String -> (String, (String, String)) -> [(String, String)]
 contains s rule =
-  [snd rule | isInfixOf (fst rule) s]
+  [snd rule | (fst rule) `isInfixOf` s]
 
 -- | The monospaced font to use as default.
 monospacedFont :: Doc
@@ -282,7 +282,7 @@ hyperlinksToDoc (x:xs) = hyp x $$ hyperlinksToDoc xs
                     ("Source","htss-"++show ident), ("Visible","true"), ("DestinationUniqueKey","1")]
                   $ inTags True "Properties" []
                   $ inTags False "BorderColor" [("type","enumeration")] (text "Black")
-                  $$ inTags False "Destination" [("type","object")] (text $ "HyperlinkURLDestination/"++(escapeColons (escapeStringForXML url))) -- HyperlinkURLDestination with more than one colon crashes CS6
+                  $$ inTags False "Destination" [("type","object")] (text $ "HyperlinkURLDestination/"++escapeColons (escapeStringForXML url)) -- HyperlinkURLDestination with more than one colon crashes CS6
 
 
 -- | Convert a list of Pandoc blocks to ICML.
diff --git a/src/Text/Pandoc/Writers/LaTeX.hs b/src/Text/Pandoc/Writers/LaTeX.hs
index de2cc3480..fa72f0f1a 100644
--- a/src/Text/Pandoc/Writers/LaTeX.hs
+++ b/src/Text/Pandoc/Writers/LaTeX.hs
@@ -41,7 +41,7 @@ import Data.Char (isAlphaNum, isAscii, isDigit, isLetter, isPunctuation, ord,
                   toLower)
 import Data.List (foldl', intercalate, intersperse, isInfixOf, nubBy,
                   stripPrefix, (\\))
-import Data.Maybe (catMaybes, fromMaybe, isJust, mapMaybe)
+import Data.Maybe (catMaybes, fromMaybe, isJust, mapMaybe, isNothing)
 import Data.Text (Text)
 import qualified Data.Text as T
 import Network.URI (unEscapeString)
@@ -401,7 +401,7 @@ elementToBeamer slideLevel  (Sec lvl _num (ident,classes,kvs) tit elts)
       let frameoptions = ["allowdisplaybreaks", "allowframebreaks", "fragile",
                           "b", "c", "t", "environment",
                           "label", "plain", "shrink", "standout"]
-      let optionslist = ["fragile" | fragile && lookup "fragile" kvs == Nothing] ++
+      let optionslist = ["fragile" | fragile && isNothing (lookup "fragile" kvs)] ++
                         [k | k <- classes, k `elem` frameoptions] ++
                         [k ++ "=" ++ v | (k,v) <- kvs, k `elem` frameoptions]
       let options = if null optionslist
@@ -819,7 +819,7 @@ listItemToLaTeX lst
   -- we need to put some text before a header if it's the first
   -- element in an item. This will look ugly in LaTeX regardless, but
   -- this will keep the typesetter from throwing an error.
-  | (Header _ _ _ :_) <- lst =
+  | (Header{} :_) <- lst =
     blockListToLaTeX lst >>= return . (text "\\item ~" $$) . nest 2
   | otherwise = blockListToLaTeX lst >>= return .  (text "\\item" $$) .
                       nest 2
@@ -856,7 +856,7 @@ sectionHeader unnumbered ident level lst = do
   plain <- stringToLaTeX TextString $ concatMap stringify lst
   let removeInvalidInline (Note _)             = []
       removeInvalidInline (Span (id', _, _) _) | not (null id') = []
-      removeInvalidInline (Image{})            = []
+      removeInvalidInline Image{}            = []
       removeInvalidInline x                    = [x]
   let lstNoNotes = foldr (mappend . (\x -> walkM removeInvalidInline x)) mempty lst
   txtNoNotes <- inlineListToLaTeX lstNoNotes
diff --git a/src/Text/Pandoc/Writers/Man.hs b/src/Text/Pandoc/Writers/Man.hs
index c1427b15c..1be955fe3 100644
--- a/src/Text/Pandoc/Writers/Man.hs
+++ b/src/Text/Pandoc/Writers/Man.hs
@@ -114,7 +114,7 @@ notesToMan :: PandocMonad m => WriterOptions -> [[Block]] -> StateT WriterState
 notesToMan opts notes =
   if null notes
      then return empty
-     else mapM (uncurry (noteToMan opts)) (zip [1..] notes) >>=
+     else zipWithM (noteToMan opts) [1..] notes >>=
           return . (text ".SH NOTES" $$) . vcat
 
 -- | Return man representation of a note.
diff --git a/src/Text/Pandoc/Writers/Muse.hs b/src/Text/Pandoc/Writers/Muse.hs
index 7c4865da8..fbebe5c20 100644
--- a/src/Text/Pandoc/Writers/Muse.hs
+++ b/src/Text/Pandoc/Writers/Muse.hs
@@ -218,7 +218,7 @@ blockToMuse (DefinitionList items) = do
         descriptionToMuse :: PandocMonad m
                           => [Block]
                           -> StateT WriterState m Doc
-        descriptionToMuse desc = (hang 4 " :: ") <$> blockListToMuse desc
+        descriptionToMuse desc = hang 4 " :: " <$> blockListToMuse desc
 blockToMuse (Header level (ident,_,_) inlines) = do
   opts <- gets stOptions
   contents <- inlineListToMuse inlines
diff --git a/src/Text/Pandoc/Writers/OOXML.hs b/src/Text/Pandoc/Writers/OOXML.hs
index 2a9b9bc84..30d8d72dd 100644
--- a/src/Text/Pandoc/Writers/OOXML.hs
+++ b/src/Text/Pandoc/Writers/OOXML.hs
@@ -104,5 +104,5 @@ fitToPage :: (Double, Double) -> Integer -> (Integer, Integer)
 fitToPage (x, y) pageWidth
   -- Fixes width to the page width and scales the height
   | x > fromIntegral pageWidth =
-    (pageWidth, floor $ ((fromIntegral pageWidth) / x) * y)
+    (pageWidth, floor $ (fromIntegral pageWidth / x) * y)
   | otherwise = (floor x, floor y)
diff --git a/src/Text/Pandoc/Writers/OpenDocument.hs b/src/Text/Pandoc/Writers/OpenDocument.hs
index e0097f507..17edc0cbd 100644
--- a/src/Text/Pandoc/Writers/OpenDocument.hs
+++ b/src/Text/Pandoc/Writers/OpenDocument.hs
@@ -594,7 +594,7 @@ paraStyle attrs = do
       tight     = if t then [ ("fo:margin-top"          , "0in"    )
                             , ("fo:margin-bottom"       , "0in"    )]
                        else []
-      indent    = if (i /= 0 || b)
+      indent    = if i /= 0 || b
                       then [ ("fo:margin-left"         , indentVal)
                            , ("fo:margin-right"        , "0in"    )
                            , ("fo:text-indent"         , "0in"    )
diff --git a/src/Text/Pandoc/Writers/Powerpoint.hs b/src/Text/Pandoc/Writers/Powerpoint.hs
index acb33f582..645a4cb86 100644
--- a/src/Text/Pandoc/Writers/Powerpoint.hs
+++ b/src/Text/Pandoc/Writers/Powerpoint.hs
@@ -1,4 +1,4 @@
-{-# LANGUAGE PatternGuards #-}
+
 
 {-
 Copyright (C) 2017-2018 Jesse Rosenthal <jrosenthal@jhu.edu>
diff --git a/src/Text/Pandoc/Writers/Powerpoint/Presentation.hs b/src/Text/Pandoc/Writers/Powerpoint/Presentation.hs
index f5f7d850f..0cf01ee01 100644
--- a/src/Text/Pandoc/Writers/Powerpoint/Presentation.hs
+++ b/src/Text/Pandoc/Writers/Powerpoint/Presentation.hs
@@ -72,7 +72,7 @@ import qualified Text.Pandoc.Shared as Shared -- so we don't overlap "Element"
 import Text.Pandoc.Writers.Shared (metaValueToInlines)
 import qualified Data.Map as M
 import qualified Data.Set as S
-import Data.Maybe (maybeToList)
+import Data.Maybe (maybeToList, fromMaybe)
 import Text.Pandoc.Highlighting
 import qualified Data.Text as T
 import Control.Applicative ((<|>))
@@ -136,7 +136,7 @@ reservedSlideIds = S.fromList [ metadataSlideId
 
 uniqueSlideId' :: Integer -> S.Set SlideId -> String -> SlideId
 uniqueSlideId' n idSet s =
-  let s' = if n == 0 then s else (s ++ "-" ++ show n)
+  let s' = if n == 0 then s else s ++ "-" ++ show n
   in if SlideId s' `S.member` idSet
      then uniqueSlideId' (n+1) idSet s
      else SlideId s'
@@ -152,7 +152,7 @@ runUniqueSlideId s = do
   return sldId
 
 addLogMessage :: LogMessage -> Pres ()
-addLogMessage msg = modify $ \st -> st{stLog = msg : (stLog st)}
+addLogMessage msg = modify $ \st -> st{stLog = msg : stLog st}
 
 type Pres = ReaderT WriterEnv (State WriterState)
 
@@ -180,7 +180,7 @@ data DocProps = DocProps { dcTitle :: Maybe String
 
 data Slide = Slide { slideId :: SlideId
                    , slideLayout :: Layout
-                   , slideNotes :: (Maybe Notes)
+                   , slideNotes :: Maybe Notes
                    } deriving (Show, Eq)
 
 newtype SlideId = SlideId String
@@ -345,12 +345,12 @@ inlineToParElems (SmallCaps ils) =
 inlineToParElems Space = inlineToParElems (Str " ")
 inlineToParElems SoftBreak = inlineToParElems (Str " ")
 inlineToParElems LineBreak = return [Break]
-inlineToParElems (Link _ ils (url, title)) = do
+inlineToParElems (Link _ ils (url, title)) =
   local (\r ->r{envRunProps = (envRunProps r){rLink = Just $ ExternalTarget (url, title)}}) $
-    inlinesToParElems ils
-inlineToParElems (Code _ str) = do
+  inlinesToParElems ils
+inlineToParElems (Code _ str) =
   local (\r ->r{envRunProps = (envRunProps r){rPropCode = True}}) $
-    inlineToParElems $ Str str
+  inlineToParElems $ Str str
 inlineToParElems (Math mathtype str) =
   return [MathElem mathtype (TeXString str)]
 inlineToParElems (Note blks) = do
@@ -409,7 +409,7 @@ blockToParagraphs (CodeBlock attr str) =
     Just sty ->
       case highlight synMap (formatSourceLines sty) attr str of
         Right pElems -> do pProps <- asks envParaProps
-                           return $ [Paragraph pProps pElems]
+                           return [Paragraph pProps pElems]
         Left _ -> blockToParagraphs $ Para [Str str]
     Nothing -> blockToParagraphs $ Para [Str str]
 -- We can't yet do incremental lists, but we should render a
@@ -463,7 +463,7 @@ blockToParagraphs (DefinitionList entries) = do
         definition <- concatMapM (blockToParagraphs . BlockQuote) blksLst
         return $ term ++ definition
   concatMapM go entries
-blockToParagraphs (Div (_, ("notes" : []), _) _) = return []
+blockToParagraphs (Div (_, "notes" : [], _) _) = return []
 blockToParagraphs (Div _ blks)  = concatMapM blockToParagraphs blks
 blockToParagraphs blk = do
   addLogMessage $ BlockNotRendered blk
@@ -481,7 +481,7 @@ multiParBullet (b:bs) = do
 
 cellToParagraphs :: Alignment -> TableCell -> Pres [Paragraph]
 cellToParagraphs algn tblCell = do
-  paras <- mapM (blockToParagraphs) tblCell
+  paras <- mapM blockToParagraphs tblCell
   let alignment = case algn of
         AlignLeft -> Just AlgnLeft
         AlignRight -> Just AlgnRight
@@ -494,7 +494,7 @@ rowToParagraphs :: [Alignment] -> [TableCell] -> Pres [[Paragraph]]
 rowToParagraphs algns tblCells = do
   -- We have to make sure we have the right number of alignments
   let pairs = zip (algns ++ repeat AlignDefault) tblCells
-  mapM (\(a, tc) -> cellToParagraphs a tc) pairs
+  mapM (uncurry cellToParagraphs) pairs
 
 withAttr :: Attr -> Shape -> Shape
 withAttr attr (Pic picPr url caption) =
@@ -507,17 +507,17 @@ withAttr _ sp = sp
 
 blockToShape :: Block -> Pres Shape
 blockToShape (Plain (il:_)) | Image attr ils (url, _) <- il =
-      (withAttr attr . Pic def url) <$> (inlinesToParElems ils)
+      (withAttr attr . Pic def url) <$> inlinesToParElems ils
 blockToShape (Para (il:_))  | Image attr ils (url, _) <- il =
-      (withAttr attr . Pic def url) <$> (inlinesToParElems ils)
+      (withAttr attr . Pic def url) <$> inlinesToParElems ils
 blockToShape (Plain (il:_)) | Link _ (il':_) target <- il
                             , Image attr ils (url, _) <- il' =
       (withAttr attr . Pic def {picPropLink = Just $ ExternalTarget target} url) <$>
-      (inlinesToParElems ils)
+      inlinesToParElems ils
 blockToShape (Para (il:_))  | Link _ (il':_) target <- il
                             , Image attr ils (url, _) <- il' =
       (withAttr attr . Pic def{picPropLink = Just $ ExternalTarget target} url) <$>
-      (inlinesToParElems ils)
+      inlinesToParElems ils
 blockToShape (Table caption algn _ hdrCells rows) = do
   caption' <- inlinesToParElems caption
   hdrCells' <- rowToParagraphs algn hdrCells
@@ -537,11 +537,11 @@ blockToShape blk = do paras <- blockToParagraphs blk
 
 combineShapes :: [Shape] -> [Shape]
 combineShapes [] = []
-combineShapes (s : []) = [s]
-combineShapes (pic@(Pic _ _ _) : ss) = pic : combineShapes ss
-combineShapes ((TextBox []) : ss) = combineShapes ss
+combineShapes[s] = [s]
+combineShapes (pic@(Pic{}) : ss) = pic : combineShapes ss
+combineShapes (TextBox [] : ss) = combineShapes ss
 combineShapes (s : TextBox [] : ss) = combineShapes (s : ss)
-combineShapes ((TextBox (p:ps)) : (TextBox (p':ps')) : ss) =
+combineShapes (TextBox (p:ps) : TextBox (p':ps') : ss) =
   combineShapes $ TextBox ((p:ps) ++ (p':ps')) : ss
 combineShapes (s:ss) = s : combineShapes ss
 
@@ -549,8 +549,8 @@ blocksToShapes :: [Block] -> Pres [Shape]
 blocksToShapes blks = combineShapes <$> mapM blockToShape blks
 
 isImage :: Inline -> Bool
-isImage (Image _ _ _) = True
-isImage (Link _ ((Image _ _ _) : _) _) = True
+isImage (Image{}) = True
+isImage (Link _ (Image _ _ _ : _) _) = True
 isImage _ = False
 
 splitBlocks' :: [Block] -> [[Block]] -> [Block] -> Pres [[Block]]
@@ -565,27 +565,27 @@ splitBlocks' cur acc (h@(Header n _ _) : blks) = do
     GT -> splitBlocks' (cur ++ [h]) acc blks
 -- `blockToParagraphs` treats Plain and Para the same, so we can save
 -- some code duplication by treating them the same here.
-splitBlocks' cur acc ((Plain ils) : blks) = splitBlocks' cur acc ((Para ils) : blks)
-splitBlocks' cur acc ((Para (il:ils)) : blks) | isImage il = do
+splitBlocks' cur acc (Plain ils : blks) = splitBlocks' cur acc (Para ils : blks)
+splitBlocks' cur acc (Para (il:ils) : blks) | isImage il = do
   slideLevel <- asks envSlideLevel
   case cur of
-    (Header n _ _) : [] | n == slideLevel ->
+    [(Header n _ _)] | n == slideLevel ->
                             splitBlocks' []
                             (acc ++ [cur ++ [Para [il]]])
-                            (if null ils then blks else (Para ils) : blks)
+                            (if null ils then blks else Para ils : blks)
     _ -> splitBlocks' []
          (acc ++ (if null cur then [] else [cur]) ++ [[Para [il]]])
-         (if null ils then blks else (Para ils) : blks)
-splitBlocks' cur acc (tbl@(Table _ _ _ _ _) : blks) = do
+         (if null ils then blks else Para ils : blks)
+splitBlocks' cur acc (tbl@(Table{}) : blks) = do
   slideLevel <- asks envSlideLevel
   case cur of
-    (Header n _ _) : [] | n == slideLevel ->
+    [(Header n _ _)] | n == slideLevel ->
                             splitBlocks' [] (acc ++ [cur ++ [tbl]]) blks
     _ ->  splitBlocks' [] (acc ++ (if null cur then [] else [cur]) ++ [[tbl]]) blks
 splitBlocks' cur acc (d@(Div (_, classes, _) _): blks) | "columns" `elem` classes =  do
   slideLevel <- asks envSlideLevel
   case cur of
-    (Header n _ _) : [] | n == slideLevel ->
+    [(Header n _ _)] | n == slideLevel ->
                             splitBlocks' [] (acc ++ [cur ++ [d]]) blks
     _ ->  splitBlocks' [] (acc ++ (if null cur then [] else [cur]) ++ [[d]]) blks
 splitBlocks' cur acc (blk : blks) = splitBlocks' (cur ++ [blk]) acc blks
@@ -594,12 +594,12 @@ splitBlocks :: [Block] -> Pres [[Block]]
 splitBlocks = splitBlocks' [] []
 
 blocksToSlide' :: Int -> [Block] -> Pres Slide
-blocksToSlide' lvl ((Header n (ident, _, _) ils) : blks)
+blocksToSlide' lvl (Header n (ident, _, _) ils : blks)
   | n < lvl = do
       registerAnchorId ident
       sldId <- asks envCurSlideId
       hdr <- inlinesToParElems ils
-      return $ Slide sldId (TitleSlide {titleSlideHeader = hdr}) Nothing
+      return $ Slide sldId TitleSlide {titleSlideHeader = hdr} Nothing
   | n == lvl = do
       registerAnchorId ident
       hdr <- inlinesToParElems ils
@@ -614,7 +614,7 @@ blocksToSlide' lvl ((Header n (ident, _, _) ils) : blks)
 blocksToSlide' _ (blk : blks)
   | Div (_, classes, _) divBlks <- blk
   , "columns" `elem` classes
-  , (Div (_, clsL, _) blksL) : (Div (_, clsR, _) blksR) : remaining <- divBlks
+  , Div (_, clsL, _) blksL : Div (_, clsR, _) blksR : remaining <- divBlks
   , "column" `elem` clsL, "column" `elem` clsR = do
       unless (null blks)
         (mapM (addLogMessage . BlockNotRendered) blks >> return ())
@@ -672,7 +672,7 @@ makeNoteEntry n blks =
   in
     case blks of
       (Para ils : blks') -> (Para $ enum : Space : ils) : blks'
-      _ -> (Para [enum]) : blks
+      _ -> Para [enum] : blks
 
 forceFontSize :: Pixels -> Pres a -> Pres a
 forceFontSize px x = do
@@ -860,7 +860,7 @@ blocksToPresentationSlides blks = do
                               (\env -> env { envCurSlideId = endNotesSlideId
                                            , envInNoteSlide = True
                                            })
-                              (blocksToSlide $ endNotesSlideBlocks)
+                              (blocksToSlide endNotesSlideBlocks)
                             return [endNotesSlide]
 
   let slides = metadataslides ++ tocSlides ++ bodyslides ++ endNotesSlides
@@ -889,9 +889,7 @@ documentToPresentation :: WriterOptions
 documentToPresentation opts (Pandoc meta blks) =
   let env = def { envOpts = opts
                 , envMetadata = meta
-                , envSlideLevel = case writerSlideLevel opts of
-                                    Just lvl -> lvl
-                                    Nothing  -> getSlideLevel blks
+                , envSlideLevel = fromMaybe (getSlideLevel blks) (writerSlideLevel opts)
                 }
       (presSlides, msgs) = runPres env def $ blocksToPresentationSlides blks
       docProps = metaToDocProps meta
diff --git a/src/Text/Pandoc/Writers/RST.hs b/src/Text/Pandoc/Writers/RST.hs
index a57527aa8..95cb46643 100644
--- a/src/Text/Pandoc/Writers/RST.hs
+++ b/src/Text/Pandoc/Writers/RST.hs
@@ -132,7 +132,7 @@ keyToRST (label, (src, _)) = do
 -- | Return RST representation of notes.
 notesToRST :: PandocMonad m => [[Block]] -> RST m Doc
 notesToRST notes =
-  mapM (uncurry noteToRST) (zip [1..] notes) >>=
+   zipWithM noteToRST [1..] notes >>=
   return . vsep
 
 -- | Return RST representation of a note.
@@ -306,8 +306,7 @@ blockToRST (OrderedList (start, style', delim) items) = do
   let maxMarkerLength = maximum $ map length markers
   let markers' = map (\m -> let s = maxMarkerLength - length m
                             in  m ++ replicate s ' ') markers
-  contents <- mapM (uncurry orderedListItemToRST) $
-              zip markers' items
+  contents <- zipWithM orderedListItemToRST markers' items
   -- ensure that sublists have preceding blank line
   return $ blankline $$ chomp (vcat contents) $$ blankline
 blockToRST (DefinitionList items) = do
@@ -356,12 +355,12 @@ blockListToRST' topLevel blocks = do
   let fixBlocks (b1:b2@(BlockQuote _):bs)
         | toClose b1 = b1 : commentSep : b2 : fixBlocks bs
         where
-          toClose (Plain{})                                = False
-          toClose (Header{})                               = False
-          toClose (LineBlock{})                            = False
-          toClose (HorizontalRule)                         = False
+          toClose Plain{}                                = False
+          toClose Header{}                               = False
+          toClose LineBlock{}                            = False
+          toClose HorizontalRule                         = False
           toClose (Para [Image _ _ (_,'f':'i':'g':':':_)]) = True
-          toClose (Para{})                                 = False
+          toClose Para{}                                 = False
           toClose _                                        = True
           commentSep  = RawBlock "rst" "..\n\n"
       fixBlocks (b:bs) = b : fixBlocks bs
diff --git a/src/Text/Pandoc/Writers/RTF.hs b/src/Text/Pandoc/Writers/RTF.hs
index 790bebc01..7006b58d1 100644
--- a/src/Text/Pandoc/Writers/RTF.hs
+++ b/src/Text/Pandoc/Writers/RTF.hs
@@ -31,6 +31,7 @@ Conversion of 'Pandoc' documents to RTF (rich text format).
 module Text.Pandoc.Writers.RTF ( writeRTF
                                ) where
 import Control.Monad.Except (catchError, throwError)
+import Control.Monad
 import qualified Data.ByteString as B
 import Data.Char (chr, isDigit, ord)
 import Data.List (intercalate, isSuffixOf)
@@ -278,8 +279,7 @@ blockToRTF indent alignment (BulletList lst) = (spaceAtEnd . concat) <$>
   mapM (listItemToRTF alignment indent (bulletMarker indent)) lst
 blockToRTF indent alignment (OrderedList attribs lst) =
   (spaceAtEnd . concat) <$>
-   mapM (uncurry (listItemToRTF alignment indent))
-   (zip (orderedMarkers indent attribs) lst)
+   zipWithM (listItemToRTF alignment indent) (orderedMarkers indent attribs) lst
 blockToRTF indent alignment (DefinitionList lst) = (spaceAtEnd . concat) <$>
   mapM (definitionListItemToRTF alignment indent) lst
 blockToRTF indent _ HorizontalRule = return $
@@ -303,8 +303,8 @@ tableRowToRTF header indent aligns sizes' cols = do
   let sizes = if all (== 0) sizes'
                  then replicate (length cols) (1.0 / fromIntegral (length cols))
                  else sizes'
-  columns <- concat <$> mapM (uncurry (tableItemToRTF indent))
-                         (zip aligns cols)
+  columns <- concat <$>
+     zipWithM (tableItemToRTF indent) aligns cols
   let rightEdges = tail $ scanl (\sofar new -> sofar + floor (new * totalTwips))
                                 (0 :: Integer) sizes
   let cellDefs = map (\edge -> (if header
diff --git a/src/Text/Pandoc/Writers/Texinfo.hs b/src/Text/Pandoc/Writers/Texinfo.hs
index b5d72aa56..bf434642e 100644
--- a/src/Text/Pandoc/Writers/Texinfo.hs
+++ b/src/Text/Pandoc/Writers/Texinfo.hs
@@ -475,7 +475,7 @@ inlineToTexinfo (Link _ txt (src@('#':_), _)) = do
 inlineToTexinfo (Link _ txt (src, _)) =
   case txt of
         [Str x] | escapeURI x == src ->  -- autolink
-             do return $ text $ "@url{" ++ x ++ "}"
+             return $ text $ "@url{" ++ x ++ "}"
         _ -> do contents <- escapeCommas $ inlineListToTexinfo txt
                 let src1 = stringToTexinfo src
                 return $ text ("@uref{" ++ src1 ++ ",") <> contents <>