Data.CaseInsensitive and (Co)Traversable

CaseInsensitive.hs

traverse :: (FoldCase s1, FoldCase s2, Functor f) => (s1 -> f s2) -> CI s1 -> f (CI s2)
traverse f = fmap CI.mk . f . CI.original

cotraverse :: (FoldCase s1, FoldCase s2, Functor f) => (f s1 -> s2) -> f (CI s1) -> CI s2
cotraverse f = CI.mk . f . fmap CI.original

-- Examples

concat :: [CI ByteString] -> CI ByteString
concat = cotraverse B.concat

intercalate :: ByteString -> [CI ByteString] -> CI ByteString
intercalate s = cotraverse (B.intercalate s)

inits :: CI ByteString -> [CI ByteString]
inits = traverse B.inits

uncons :: CI ByteString -> Maybe (Word8, CI ByteString)
uncons = getCompose . traverse (Compose . B.uncons)

transpose :: [CI ByteString] -> [CI ByteString]
transpose = undefined -- ??