xcodec change log:

Major release 1.0

Version 1.0.0.0 (05-21-2026)

Introducing this package to hackage.org! This module provides instances of BinaryTranscoder, a type-class for generically working on binary data formats, and StreamTranscoder a type-class interface for designing encoders and decoders on top of BinaryTranscoder.

Module Data.XCodec.BinaryTranscoder

This module provides the type-class for the BinaryTranscoder. It also provides default instances for ByteString, LazyByteString, and ShortByteString from the GHC standard library. The minimal definition for a BinaryTranscoder is currently with the following methods (where bxc is the type-parameter deriving BinaryTranscoder):

-- | Gives back the length in bytes of the Transcoder data.
lengthBytes :: bxc -> Int
-- | Unpacks transcoder data as BitSet, ie, an infinite bitarray.
unpackValue :: bxc -> BitSet
-- | Places the contents of the transcoder into a ByteString Builder.
serializeValue :: bxc -> Builder
-- | Packs Word8 values into transcoder data `bxc`.
packBytes :: [Word8] -> bxc
-- | Unpacks transcoder data into a list of bytes.
unpackBytes :: bxc -> [Word8]
-- | Prepends a byte value to the top of the transcoder data.
pushByte :: bxc -> Word8 -> bxc
-- | Appends the byte value to the end of the transcoder data.
pushByteEnd :: bxc -> Word8 -> bxc
-- | Takes a subsection of bytes from the beginning of the transcoder data.
takeBytes :: Int -> bxc -> bxc
-- | Removes bytes from the beginning of transcoder data.
dropBytes :: Int -> bxc -> bxc
-- | Removes bytes from the end of transcoder data.
takeBytesEnd :: Int -> bxc -> bxc
-- | Removes bytes from the end of transcoder data.
dropBytesEnd :: Int -> bxc -> bxc
-- | Parititions the binary data at the nth byte.
splitAtByte :: Int -> bxc -> (bxc, bxc)
-- | Repeats a byte value in binary data.
replicateByte :: Int -> Word8 -> bxc
-- | Splits byte values based on the first false result from the predicate.
spanBytes :: (Word8 -> Bool) -> bxc -> (bxc, bxc)
-- | Splits the list while the element predicate holds staring from the left
-- side.
spanBytesEnd :: (Word8 -> Bool) -> bxc -> (bxc, bxc)

Module Data.XCodec.StreamTranscoder

This module exports the type-class and methods for StreamTranscoder. It provides no default instances, and is a way for the programmer to implement generic decoders and decoders on streams of data from deriving from the BinaryTranscoder class of types. It defines the follwing method signatures:

-- | Generic Encoder signature
type Encoder xtype ytype = xtype -> ytype

-- | Generic Decoder signature
type Decoder xtype ytype = ytype -> Maybe xtype

-- | StreamTranscoder give a way to make a generic codec methods.
class (BinaryTranscoder xtype) => StreamTranscoder codec xtype ytype where
  streamEncoder :: codec -> Encoder xtype ytype
  streamDecoder :: codec -> Decoder xtype ytype