length +bytestring

length :: ByteString -> Int
bytestring Data.ByteString, bytestring Data.ByteString.Char8
O(1) length returns the length of a ByteString as an Int.
length :: ByteString -> Int64
bytestring Data.ByteString.Lazy, bytestring Data.ByteString.Lazy.Char8
O(n\c)/ length returns the length of a ByteString as an Int64