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

@@ -94,17 +94,19 @@ 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]
+frontpage meta' = do
   t <- cMapM toXml . docTitle $ meta'
   return $
     [ el "title" (el "p" t)
     , el "annotation" (map (el "p" . cMap plain)
                        (docAuthors meta' ++ [docDate meta']))
     ]
-  description :: Meta -> FBM Content
+
-  description meta' = do
+description :: Meta -> FBM Content
+description meta' = do
   bt <- booktitle meta'
   let as = authors meta'
   dd <- docdate meta'
@@ -112,16 +114,19 @@ writeFB2 opts (Pandoc meta blocks) = flip evalStateT newFB $ do
     [ el "title-info" (bt ++ as ++ dd)
     , el "document-info" [ el "program-used" "pandoc" ] -- FIXME: +version
     ]
-  booktitle :: Meta -> FBM [Content]
+
-  booktitle meta' = do
+booktitle :: Meta -> FBM [Content]
+booktitle meta' = do
   t <- cMapM toXml . docTitle $ meta'
   return $ if null t
            then []
            else [ el "book-title" t ]
-  authors :: Meta -> [Content]
+
-  authors meta' = cMap author (docAuthors meta')
+authors :: Meta -> [Content]
-  author :: [Inline] -> [Content]
+authors meta' = cMap author (docAuthors meta')
-  author ss =
+
+author :: [Inline] -> [Content]
+author ss =
   let ws = words . cMap plain $ ss
       email = (el "email") `fmap` (take 1 $ filter ('@' `elem`) ws)
       ws' = filter ('@' `notElem`) ws
@@ -134,8 +139,9 @@ writeFB2 opts (Pandoc meta blocks) = flip evalStateT newFB $ do
                                 , el "last-name" (last rest) ]
                 ([]) -> []
   in  list $ el "author" (names ++ email)
-  docdate :: Meta -> FBM [Content]
+
-  docdate meta' = do
+docdate :: Meta -> FBM [Content]
+docdate meta' = do
   let ss = docDate meta'
   d <- cMapM toXml ss
   return $ if null d