Data.UUID.LittleEndian

Codec functions

toByteString :: UUID -> ByteString

Encode a UUID into a ByteString in little-endian-ish byte order.

fromByteString :: ByteString -> Maybe UUID

Extract a UUID from a ByteString in little-endian-ish byte order. The argument must be 16 bytes long, otherwise Nothing is returned.

toWords :: UUID -> (Word32, Word32, Word32, Word32)

Covert a UUID into a sequence of Word32 values. When stored in network byte order, this tuple encodes the UUID in little-endian-ish byte order.

fromWords :: Word32 -> Word32 -> Word32 -> Word32 -> UUID

Create a UUID from a sequence of Word32 values. The opposite of toWords.

Re-exported entities from uuid

Nota bene: the Storable and Binary instances of UUID use the encoding specified in RFC 4122, rather than the little-endian-ish encoding.

data UUID

The UUID type. A Random instance is provided which produces version 4 UUIDs as specified in RFC 4122. The Storable and Binary instances are compatible with RFC 4122, storing the fields in network order as 16 bytes.

Instances

Eq UUID

Data UUID

Ord UUID

Read UUID

Show UUID

Typeable UUID

Storable UUID

Binary UUID

NFData UUID

Hashable UUID

Random UUID

toString :: UUID -> String

Convert a UUID into a hypenated string using lower-case letters. Example:

  toString <$> fromString "550e8400-e29b-41d4-a716-446655440000"

fromString :: String -> Maybe UUID

If the passed in String can be parsed as a UUID, it will be. The hyphens may not be omitted. Example:

  fromString "c2cc10e1-57d6-4b6f-9899-38d972112d8c"

Hex digits may be upper or lower-case.

toASCIIBytes :: UUID -> ByteString

Convert a UUID into a hyphentated string using lower-case letters, packed as ASCII bytes into ByteString.

This should be equivalent to toString with pack.

fromASCIIBytes :: ByteString -> Maybe UUID

If the passed in ByteString can be parsed as an ASCII representation of a UUID, it will be. The hyphens may not be omitted.

This should be equivalent to fromString with unpack.

toLazyASCIIBytes :: UUID -> ByteString

Similar to toASCIIBytes except we produce a lazy ByteString.

fromLazyASCIIBytes :: ByteString -> Maybe UUID

Similar to fromASCIIBytes except parses from a lazy ByteString.

null :: UUID -> Bool

Returns true if the passed-in UUID is the nil UUID.

nil :: UUID

The nil UUID, as defined in RFC 4122. It is a UUID of all zeros. null u iff u == nil.

Endianity tools

swapTupleEndianity :: (Word32, Word32, Word32, Word32) -> (Word32, Word32, Word32, Word32)

Swaps the endianity of a UUID Word32 tuple.

swapListEndianity :: [Word8] -> [Word8]

Swaps the endianity of a UUID byte list, if the list is at least eight bytes long. Otherwise, it returns the original list.