diff --git a/binary-file.cabal b/binary-file.cabal
--- a/binary-file.cabal
+++ b/binary-file.cabal
@@ -2,7 +2,7 @@
 cabal-version:	>= 1.8
 
 name:		binary-file
-version:	0.15.18
+version:	0.15.22
 stability:	experimental
 author:		Yoshikuni Jujo <PAF01143@nifty.ne.jp>
 maintainer:	Yoshikuni Jujo <PAF01143@nifty.ne.jp>
@@ -92,18 +92,20 @@
 source-repository	this
     type:	git
     location:	git://github.com/YoshikuniJujo/binary-file.git
-    tag:	0.15.18
+    tag:	0.15.22
 
 library
     hs-source-dirs:	src
     exposed-modules:
-        File.Binary,
+        File.Binary
         File.Binary.Instances
-        File.Binary.Instances.LittleEndian,
+        File.Binary.Instances.LittleEndian
         File.Binary.Instances.BigEndian
+        File.Binary.Instances.LSB0
+        File.Binary.Instances.MSB0
     other-modules:
-        File.Binary.Classes,
-        File.Binary.Parse,
+        File.Binary.Classes
+        File.Binary.Parse
         File.Binary.Quote
     build-depends:	base > 3 && < 5, template-haskell, peggy, bytestring,
         monads-tf
diff --git a/src/File/Binary/Classes.hs b/src/File/Binary/Classes.hs
--- a/src/File/Binary/Classes.hs
+++ b/src/File/Binary/Classes.hs
@@ -15,11 +15,11 @@
 
 class Field f where
 	type FieldArgument f
-	fromBinary :: (Binary b, Functor m, Monad m) => FieldArgument f -> b -> m (f, b)
-	toBinary :: (Binary b, Functor m, Monad m) => FieldArgument f -> f -> m b
-	fromBits :: (Binary b, Functor m, Monad m) =>
+	fromBinary :: (Binary b, Applicative m, Monad m) => FieldArgument f -> b -> m (f, b)
+	toBinary :: (Binary b, Applicative m, Monad m) => FieldArgument f -> f -> m b
+	fromBits :: (Binary b, Applicative m, Monad m) =>
 		FieldArgument f -> AddBits b -> m (f, AddBits b)
-	consToBits :: (Binary b, Functor m, Monad m) =>
+	consToBits :: (Binary b, Applicative m, Monad m) =>
 		FieldArgument f -> f -> AddBits b -> m (AddBits b)
 
 	fromBits a ([], b) = second ([] ,) `liftM` fromBinary a b
diff --git a/src/File/Binary/Instances.hs b/src/File/Binary/Instances.hs
--- a/src/File/Binary/Instances.hs
+++ b/src/File/Binary/Instances.hs
@@ -53,7 +53,9 @@
 	consToBits (a, _) fs ret = foldM (flip $ consToBits a) ret $ reverse fs
 
 times :: Monad m => Int -> (s -> m (ret, s)) -> s -> m ([ret], s)
-times n f = runStateT $ replicateM n (StateT f)
+times n f
+	| n >= 0 = runStateT $ replicateM n (StateT f)
+	| otherwise = error "times: negative times?"
 
 whole :: (Functor m, Monad m, Eq s) => s -> (s -> m (ret, s)) -> s -> m ([ret], s)
 whole e f = runStateT $ do
diff --git a/src/File/Binary/Instances/BigEndian.hs b/src/File/Binary/Instances/BigEndian.hs
--- a/src/File/Binary/Instances/BigEndian.hs
+++ b/src/File/Binary/Instances/BigEndian.hs
@@ -1,9 +1,9 @@
 {-# LANGUAGE TypeFamilies #-}
 {-# OPTIONS_GHC -fno-warn-orphans #-}
 
-module File.Binary.Instances.BigEndian (BitsInt) where
+module File.Binary.Instances.BigEndian () where
 
-import File.Binary.Classes (Field(..), Binary(..), pop, push)
+import File.Binary.Classes (Field(..), Binary(..))
 import Data.ByteString.Lazy (pack, unpack)
 import Data.Word (Word8, Word32)
 import Data.Bits (Bits, (.&.), (.|.), shiftL, shiftR)
@@ -34,47 +34,3 @@
 	where
 	itw r 0 _ = r
 	itw r n i = itw (fromIntegral (i .&. 0xff) : r) (n - 1) (i `shiftR` 8)
-
-instance Field Bool where
-	type FieldArgument Bool = ()
-	fromBits () ([], bin) = fromBits () $ pop bin
-	fromBits () (bs, bin) = return (last bs, (init bs, bin))
-	consToBits () b (bs, bin)
-		| length bs == 7 = return ([], push (bs ++ [b], bin))
-		| otherwise = return (bs ++ [b], bin)
-
-data BitsInt = BitsInt { bitsInt :: Int } deriving Show
-
-instance Eq BitsInt where
-	BitsInt i1 == BitsInt i2 = i1 == i2
-
-instance Num BitsInt where
-	BitsInt i1 + BitsInt i2 = BitsInt $ i1 + i2
-	BitsInt i1 * BitsInt i2 = BitsInt $ i1 * i2
-	abs (BitsInt i) = BitsInt $ abs i
-	signum (BitsInt i) = BitsInt $ signum i
-	fromInteger i = BitsInt $ fromInteger i
-
-instance Field BitsInt where
-	type FieldArgument BitsInt = Int
-	fromBits n = return . first BitsInt . fb n 0
-	consToBits n = ctb n . bitsInt
-
-fromEnum' :: (Enum e, Num i) => e -> i
-fromEnum' = fromIntegral . fromEnum
-
-toEnum' :: (Enum e, Integral i) => i -> e
-toEnum' = toEnum . fromIntegral
-
-fb :: (Bits f, Num f, Binary b) => Int -> f -> ([Bool], b) -> (f, ([Bool], b))
-fb 0 r bb = (r, bb)
-fb n r ([], b) = fb n r $ pop b
-fb n r (bs, b) = fb (n - 1) (r `shiftL` 1 .|. fromEnum' (last bs)) (init bs, b)
-
-ctb :: (Bits f, Integral f, Binary b, Functor m, Monad m) =>
-	Int -> f -> ([Bool], b) -> m ([Bool], b)
-ctb 0 _ r = return r
-ctb n f (bs, b)
-	| length bs == 7 = ctb (n - 1) (f `shiftR` 1) ([], push (bs ++ [bit], b))
-	| otherwise = ctb (n - 1) (f `shiftR` 1) (bs ++ [bit], b)
-	where bit = toEnum' $ f .&. 1
diff --git a/src/File/Binary/Instances/LSB0.hs b/src/File/Binary/Instances/LSB0.hs
new file mode 100644
--- /dev/null
+++ b/src/File/Binary/Instances/LSB0.hs
@@ -0,0 +1,43 @@
+{-# LANGUAGE TypeFamilies #-}
+{-# OPtIONS_GHC -fno-warn-orphans #-}
+
+module File.Binary.Instances.LSB0 (BitsInt, bitsInt) where
+
+import File.Binary.Classes
+import Data.Bits
+import Control.Arrow
+import Control.Monad
+
+instance Field Bool where
+	type FieldArgument Bool = ()
+	fromBits () ([], bin) = fromBits () $ pop bin
+	fromBits () (b : bs, bin) = return (b, (bs, bin))
+	consToBits () b (bs, bin)
+		| length bs == 7 = return ([], push (b : bs, bin))
+		| otherwise = return (b : bs, bin)
+
+newtype BitsInt = BitsInt { bitsInt :: Int } deriving Show
+
+instance Eq BitsInt where
+	BitsInt i1 == BitsInt i2 = i1 == i2
+
+instance Num BitsInt where
+	BitsInt i1 + BitsInt i2 = BitsInt $ i1 + i2
+	BitsInt i1 * BitsInt i2 = BitsInt $ i1 * i2
+	abs (BitsInt i) = BitsInt $ abs i
+	signum (BitsInt i) = BitsInt $ signum i
+	fromInteger i = BitsInt $ fromInteger i
+
+instance Field BitsInt where
+	type FieldArgument BitsInt = Int
+	fromBits 0 bb = return (BitsInt 0, bb)
+	fromBits n ([], bin) = fromBits n $ pop bin
+	fromBits n (b : bs, bin) = first
+		(BitsInt . (fromEnum b .|.) . (`shiftL` 1) . bitsInt) `liftM`
+		fromBits (n - 1) (bs, bin)
+	consToBits 0 _ bb = return bb
+	consToBits n (BitsInt f) bb = do
+		(bs, bin) <- consToBits (n - 1) (BitsInt $ f `shiftR` 1) bb
+		return $ if length bs == 7
+			then ([], push (toEnum (f .&. 1) : bs, bin))
+			else (toEnum (f .&. 1) : bs, bin)
diff --git a/src/File/Binary/Instances/LittleEndian.hs b/src/File/Binary/Instances/LittleEndian.hs
--- a/src/File/Binary/Instances/LittleEndian.hs
+++ b/src/File/Binary/Instances/LittleEndian.hs
@@ -1,14 +1,13 @@
 {-# LANGUAGE TypeFamilies #-}
 {-# OPTIONS_GHC -fno-warn-orphans #-}
 
-module File.Binary.Instances.LittleEndian (BitsInt) where
+module File.Binary.Instances.LittleEndian () where
 
-import File.Binary.Classes (Field(..), Binary(..), pop, push)
+import File.Binary.Classes (Field(..), Binary(..))
 import Data.ByteString.Lazy (pack, unpack)
 import Data.Word (Word8, Word32)
 import Data.Bits (Bits, (.&.), (.|.), shiftL, shiftR)
 import Control.Arrow (first)
-import Control.Monad
 
 instance Field Int where
 	type FieldArgument Int = Int
@@ -31,37 +30,3 @@
 intToWords :: (Bits i, Integral i) => Int -> i -> [Word8]
 intToWords 0 _ = []
 intToWords n i = fromIntegral (i .&. 0xff) : intToWords (n - 1) (i `shiftR` 8)
-
-instance Field Bool where
-	type FieldArgument Bool = ()
-	fromBits () ([], bin) = fromBits () $ pop bin
-	fromBits () (b : bs, bin) = return (b, (bs, bin))
-	consToBits () b (bs, bin)
-		| length bs == 7 = return ([], push (b : bs, bin))
-		| otherwise = return (b : bs, bin)
-
-newtype BitsInt = BitsInt { bitsInt :: Int } deriving Show
-
-instance Eq BitsInt where
-	BitsInt i1 == BitsInt i2 = i1 == i2
-
-instance Num BitsInt where
-	BitsInt i1 + BitsInt i2 = BitsInt $ i1 + i2
-	BitsInt i1 * BitsInt i2 = BitsInt $ i1 * i2
-	abs (BitsInt i) = BitsInt $ abs i
-	signum (BitsInt i) = BitsInt $ signum i
-	fromInteger i = BitsInt $ fromInteger i
-
-instance Field BitsInt where
-	type FieldArgument BitsInt = Int
-	fromBits 0 bb = return (BitsInt 0, bb)
-	fromBits n ([], bin) = fromBits n $ pop bin
-	fromBits n (b : bs, bin) = first
-		(BitsInt . (fromEnum b .|.) . (`shiftL` 1) . bitsInt) `liftM`
-		fromBits (n - 1) (bs, bin)
-	consToBits 0 _ bb = return bb
-	consToBits n (BitsInt f) bb = do
-		(bs, bin) <- consToBits (n - 1) (BitsInt $ f `shiftR` 1) bb
-		return $ if length bs == 7
-			then ([], push (toEnum (f .&. 1) : bs, bin))
-			else (toEnum (f .&. 1) : bs, bin)
diff --git a/src/File/Binary/Instances/MSB0.hs b/src/File/Binary/Instances/MSB0.hs
new file mode 100644
--- /dev/null
+++ b/src/File/Binary/Instances/MSB0.hs
@@ -0,0 +1,52 @@
+{-# LANGUAGE TypeFamilies #-}
+{-# OPTIONS_GHC -fno-warn-orphans #-}
+
+module File.Binary.Instances.MSB0 (BitsInt) where
+
+import File.Binary.Classes
+import Data.Bits (Bits, shiftL, shiftR, (.|.), (.&.))
+import Control.Arrow
+
+instance Field Bool where
+	type FieldArgument Bool = ()
+	fromBits () ([], bin) = fromBits () $ pop bin
+	fromBits () (bs, bin) = return (last bs, (init bs, bin))
+	consToBits () b (bs, bin)
+		| length bs == 7 = return ([], push (bs ++ [b], bin))
+		| otherwise = return (bs ++ [b], bin)
+
+data BitsInt = BitsInt { bitsInt :: Int } deriving Show
+
+instance Eq BitsInt where
+	BitsInt i1 == BitsInt i2 = i1 == i2
+
+instance Num BitsInt where
+	BitsInt i1 + BitsInt i2 = BitsInt $ i1 + i2
+	BitsInt i1 * BitsInt i2 = BitsInt $ i1 * i2
+	abs (BitsInt i) = BitsInt $ abs i
+	signum (BitsInt i) = BitsInt $ signum i
+	fromInteger i = BitsInt $ fromInteger i
+
+instance Field BitsInt where
+	type FieldArgument BitsInt = Int
+	fromBits n = return . first BitsInt . fb n 0
+	consToBits n = ctb n . bitsInt
+
+fromEnum' :: (Enum e, Num i) => e -> i
+fromEnum' = fromIntegral . fromEnum
+
+toEnum' :: (Enum e, Integral i) => i -> e
+toEnum' = toEnum . fromIntegral
+
+fb :: (Bits f, Num f, Binary b) => Int -> f -> ([Bool], b) -> (f, ([Bool], b))
+fb 0 r bb = (r, bb)
+fb n r ([], b) = fb n r $ pop b
+fb n r (bs, b) = fb (n - 1) (r `shiftL` 1 .|. fromEnum' (last bs)) (init bs, b)
+
+ctb :: (Bits f, Integral f, Binary b, Functor m, Monad m) =>
+	Int -> f -> ([Bool], b) -> m ([Bool], b)
+ctb 0 _ r = return r
+ctb n f (bs, b)
+	| length bs == 7 = ctb (n - 1) (f `shiftR` 1) ([], push (bs ++ [bit], b))
+	| otherwise = ctb (n - 1) (f `shiftR` 1) (bs ++ [bit], b)
+	where bit = toEnum' $ f .&. 1
diff --git a/src/File/Binary/Parse.hs b/src/File/Binary/Parse.hs
--- a/src/File/Binary/Parse.hs
+++ b/src/File/Binary/Parse.hs
@@ -85,7 +85,7 @@
 	= emp var sp '::' sp typ	{ ($2, $5) }
 	/ ''				{ ("_", conT $ mkName "()") }
 
-dat :: SItem = emp ex? sp typS sp ':' sp val
+dat :: SItem = emp ex? spn typS sp ':' spn val
 	{ SItem (fromMaybe (return $ conE $ mkName "()") $2) ($7, $4) }
 --	{ SItem (fromMaybe (return $ conE $ mkName "()") $2) $
 --		either Left (Right . second (const $4)) $7 }
@@ -152,6 +152,7 @@
 ln :: String = [A-Z][_a-zA-Z0-9]*			{ $1 : $2 }
 sn :: String = [_a-z][_a-zA-Z0-9]*			{ $1 : $2 }
 
+spn :: () = (comm / [ \t\n])*				{ () }
 sp :: () = (comm / [ \t])*				{ () }
 emp :: () = (comm / lcomm / [ \n])*			{ () }
 lcomm :: Char = '--' [^\n]* [\n]			{ ' ' }