Added solution to rubyquiz6 GEDCOM parser

GedcomParser.hs

@@ -12,27 +12,27 @@ import System.IO
 
 -- a line in a GEDCOM document
 data Line = Line {
-				lineLevel :: Int,
-				lineTag :: String,
-				lineValue :: Maybe String,
-				lineId :: Maybe String
-			} deriving (Show)
+                lineLevel :: Int,
+                lineTag :: String,
+                lineValue :: Maybe String,
+                lineId :: Maybe String
+            } deriving (Show)
 
 -- an element in a GEDCOM document
 data Elem = Elem {
-				elemTag :: String,
-				elemValue :: Maybe String,
-				elemId :: Maybe String,
-				elemChildren :: [Elem]
-			} deriving (Show)
+                elemTag :: String,
+                elemValue :: Maybe String,
+                elemId :: Maybe String,
+                elemChildren :: [Elem]
+            } deriving (Show)
 
 indent n = concat . (replicate n) $ "  "
 
 trimValue value = case value of
-	Nothing -> Nothing
-	Just v
-		| v == "" -> Nothing
-		| otherwise -> Just v
+    Nothing -> Nothing
+    Just v
+        | v == "" -> Nothing
+        | otherwise -> Just v
 
 normalizeValue = maybe "" id
 
@@ -41,23 +41,23 @@ whitespaces = many (char ' ' <|> tab <|> newline)
 
 -- parses a line
 line level = do
-	string (show level)
-	spaces
-	id <- optionMaybe $ between (char '@') (char '@') (many1 alphaNum)
-	spaces
-	tag <- many1 upper
-	spaces
-	value <- fmap trimValue $ optionMaybe $ manyTill (anyChar) newline
-	return $ Line level tag value id
+    string (show level)
+    spaces
+    id <- optionMaybe $ between (char '@') (char '@') (many1 alphaNum)
+    spaces
+    tag <- many1 upper
+    spaces
+    value <- fmap trimValue $ optionMaybe $ manyTill (anyChar) newline
+    return $ Line level tag value id
 
 -- parses an element
 element level = do
-	ml <- optionMaybe $ line level
-	case ml of
-		Nothing -> fail ("invalid level " ++ show level)
-		Just Line{..} -> do
-			children <- many (element $ level + 1)
-			return $ Elem lineTag lineValue lineId children
+    ml <- optionMaybe $ line level
+    case ml of
+        Nothing -> fail ("invalid level " ++ show level)
+        Just Line{..} -> do
+            children <- many (element $ level + 1)
+            return $ Elem lineTag lineValue lineId children
 
 -- parses a document
 document = (element 0) `endBy` whitespaces
@@ -65,44 +65,44 @@ document = (element 0) `endBy` whitespaces
 -- normalizes an element by merging values of CONC and CONT
 -- elements with parent element value
 normalizeElem element =
-	let
-		conChildren = filter concOrCont $ elemChildren element
-		text = foldl (\t el -> t
-						++ (if elemTag el == "CONC" then "\n" else " ")
-						++ normalizeValue (elemValue el))
-		 			"" conChildren
-		nonConChildren = filter (not . concOrCont) $ elemChildren element
-	in
-		element { elemValue = trimValue $
-						Just (normalizeValue (elemValue element) ++ text),
-			   	  elemChildren = map normalizeElem nonConChildren }
-	where
-		concOrCont el = elemTag el `elem` ["CONC", "CONT"]
+    let
+        conChildren = filter concOrCont $ elemChildren element
+        text = foldl (\t el -> t
+                        ++ (if elemTag el == "CONC" then "\n" else " ")
+                        ++ normalizeValue (elemValue el))
+                    "" conChildren
+        nonConChildren = filter (not . concOrCont) $ elemChildren element
+    in
+        element { elemValue = trimValue $
+                        Just (normalizeValue (elemValue element) ++ text),
+                  elemChildren = map normalizeElem nonConChildren }
+    where
+        concOrCont el = elemTag el `elem` ["CONC", "CONT"]
 
 -- normalizes a document
 normalizeDoc = map normalizeElem
 
 -- converts an element to XML
 elemToXml indentation Elem{..} =
-	indent indentation
-	++ "<" ++ elemTag
-	++ maybe "" (\i -> " id=\"@" ++ i ++ "@\"") elemId
-	++ case elemChildren of
-		[] -> ">" ++ normalizeValue elemValue ++ "</" ++ elemTag ++ ">"
-		_ -> maybe "" (\v -> " value=\"" ++ v ++ "\"") elemValue ++ ">\n"
-			++ unlines (map (elemToXml (indentation + 1)) elemChildren)
-			++ indent indentation ++ "</" ++ elemTag ++ ">"
+    indent indentation
+    ++ "<" ++ elemTag
+    ++ maybe "" (\i -> " id=\"@" ++ i ++ "@\"") elemId
+    ++ case elemChildren of
+        [] -> ">" ++ normalizeValue elemValue ++ "</" ++ elemTag ++ ">"
+        _ -> maybe "" (\v -> " value=\"" ++ v ++ "\"") elemValue ++ ">\n"
+            ++ unlines (map (elemToXml (indentation + 1)) elemChildren)
+            ++ indent indentation ++ "</" ++ elemTag ++ ">"
 
 -- converts a document to XML
 documentToXml doc = "<DOCUMENT>\n"
-	++ (unlines . map (elemToXml 1) $ doc)
-	++ "</DOCUMENT>"
+    ++ (unlines . map (elemToXml 1) $ doc)
+    ++ "</DOCUMENT>"
 
 -- converts a GEDCOM document supplied through STDIN into XML
 -- and prints to STDOUT
 main = do
-	text <- getContents
-	case parse document "GEDCOM Parser" text of
-		Right []  -> return ()
-		Right doc -> putStrLn $ documentToXml (normalizeDoc doc)
-		Left e    -> print e
+    text <- getContents
+    case parse document "GEDCOM Parser" text of
+        Right []  -> return ()
+        Right doc -> putStrLn $ documentToXml (normalizeDoc doc)
+        Left e    -> print e