FB2 writer: bring functions to toplevel.

This is the first of a number of changes to bring the FB2 writer a bit
closer to the idioms used elsewhere in pandoc, so it can be more easily
converted to using the pure functions from Free.

src/Text/Pandoc/Writers/FB2.hs

@@ -94,53 +94,59 @@ writeFB2 opts (Pandoc meta blocks) = flip evalStateT newFB $ do
           xlink = "http://www.w3.org/1999/xlink"
       in  [ uattr "xmlns" xmlns
           , attr ("xmlns", "l") xlink ]
-  --
+
-  frontpage :: Meta -> FBM [Content]
+
-  frontpage meta' = do
+frontpage :: Meta -> FBM [Content]
-      t <- cMapM toXml . docTitle $ meta'
+frontpage meta' = do
-      return $
+  t <- cMapM toXml . docTitle $ meta'
-        [ el "title" (el "p" t)
+  return $
-        , el "annotation" (map (el "p" . cMap plain)
+    [ el "title" (el "p" t)
-                           (docAuthors meta' ++ [docDate meta']))
+    , el "annotation" (map (el "p" . cMap plain)
-        ]
+                       (docAuthors meta' ++ [docDate meta']))
-  description :: Meta -> FBM Content
+    ]
-  description meta' = do
+
-      bt <- booktitle meta'
+description :: Meta -> FBM Content
-      let as = authors meta'
+description meta' = do
-      dd <- docdate meta'
+  bt <- booktitle meta'
-      return $ el "description"
+  let as = authors meta'
-         [ el "title-info" (bt ++ as ++ dd)
+  dd <- docdate meta'
-         , el "document-info" [ el "program-used" "pandoc" ] -- FIXME: +version
+  return $ el "description"
-         ]
+    [ el "title-info" (bt ++ as ++ dd)
-  booktitle :: Meta -> FBM [Content]
+    , el "document-info" [ el "program-used" "pandoc" ] -- FIXME: +version
-  booktitle meta' = do
+    ]
-      t <- cMapM toXml . docTitle $ meta'
+
-      return $ if null t
+booktitle :: Meta -> FBM [Content]
-               then []
+booktitle meta' = do
-               else [ el "book-title" t ]
+  t <- cMapM toXml . docTitle $ meta'
-  authors :: Meta -> [Content]
+  return $ if null t
-  authors meta' = cMap author (docAuthors meta')
+           then []
-  author :: [Inline] -> [Content]
+           else [ el "book-title" t ]
-  author ss =
+
-      let ws = words . cMap plain $ ss
+authors :: Meta -> [Content]
-          email = (el "email") `fmap` (take 1 $ filter ('@' `elem`) ws)
+authors meta' = cMap author (docAuthors meta')
-          ws' = filter ('@' `notElem`) ws
+
-          names = case ws' of
+author :: [Inline] -> [Content]
-                    (nickname:[]) -> [ el "nickname" nickname ]
+author ss =
-                    (fname:lname:[]) -> [ el "first-name" fname
+  let ws = words . cMap plain $ ss
-                                       , el "last-name" lname ]
+      email = (el "email") `fmap` (take 1 $ filter ('@' `elem`) ws)
-                    (fname:rest) -> [ el "first-name" fname
+      ws' = filter ('@' `notElem`) ws
-                                   , el "middle-name" (concat . init $ rest)
+      names = case ws' of
-                                   , el "last-name" (last rest) ]
+                (nickname:[]) -> [ el "nickname" nickname ]
-                    ([]) -> []
+                (fname:lname:[]) -> [ el "first-name" fname
-      in  list $ el "author" (names ++ email)
+                                    , el "last-name" lname ]
-  docdate :: Meta -> FBM [Content]
+                (fname:rest) -> [ el "first-name" fname
-  docdate meta' = do
+                                , el "middle-name" (concat . init $ rest)
-      let ss = docDate meta'
+                                , el "last-name" (last rest) ]
-      d <- cMapM toXml ss
+                ([]) -> []
-      return $ if null d
+  in  list $ el "author" (names ++ email)
-               then []
+
-               else [el "date" d]
+docdate :: Meta -> FBM [Content]
+docdate meta' = do
+  let ss = docDate meta'
+  d <- cMapM toXml ss
+  return $ if null d
+           then []
+           else [el "date" d]
 
 -- | Divide the stream of blocks into sections and convert to XML
 -- representation.