hlint code improvements.

16 files changed, 75 insertions, 83 deletions

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 <>