1 files changed, 2 insertions, 4 deletions

diff --git a/lib/Data/Packed/Internal/Vector.hs b/lib/Data/Packed/Internal/Vector.hs
index 652b980..ac2d0d7 100644
--- a/lib/Data/Packed/Internal/Vector.hs
+++ b/lib/Data/Packed/Internal/Vector.hs
@@ -71,11 +71,11 @@ data Vector t =
       , fptr :: {-# UNPACK #-} !(ForeignPtr t)   -- ^ foreign pointer to the memory block
       }
 
-unsafeToForeignPtr :: Vector a -> (ForeignPtr a, Int, Int)
+unsafeToForeignPtr :: Storable a => Vector a -> (ForeignPtr a, Int, Int)
 unsafeToForeignPtr v = (fptr v, ioff v, idim v)
 
 -- | Same convention as in Roman Leshchinskiy's vector package.
-unsafeFromForeignPtr :: ForeignPtr a -> Int -> Int -> Vector a
+unsafeFromForeignPtr :: Storable a => ForeignPtr a -> Int -> Int -> Vector a
 unsafeFromForeignPtr fp i n | n > 0 = V {ioff = i, idim = n, fptr = fp}
                             | otherwise = error "unsafeFromForeignPtr with dim < 1"
 
@@ -266,13 +266,11 @@ takesV ms w | sum ms > dim w = error $ "takesV " ++ show ms ++ " on dim = " ++ (
 
 -- | transforms a complex vector into a real vector with alternating real and imaginary parts 
 asReal :: (RealFloat a, Storable a) => Vector (Complex a) -> Vector a
---asReal v = V { ioff = 2*ioff v, idim = 2*dim v, fptr =  castForeignPtr (fptr v) }
 asReal v = unsafeFromForeignPtr (castForeignPtr fp) (2*i) (2*n)
     where (fp,i,n) = unsafeToForeignPtr v
 
 -- | transforms a real vector into a complex vector with alternating real and imaginary parts
 asComplex :: (RealFloat a, Storable a) => Vector a -> Vector (Complex a)
---asComplex v = V { ioff = ioff v `div` 2, idim = dim v `div` 2, fptr =  castForeignPtr (fptr v) }
 asComplex v = unsafeFromForeignPtr (castForeignPtr fp) (i `div` 2) (n `div` 2)
     where (fp,i,n) = unsafeToForeignPtr v