Data.Vector.Compact.Blob

Blobs are raw data in continuous regions of memory.

This library provides a type for blobs consisting 64 bit words which is optimized for small sizes. They take:

• only 1 extra word up for blobs of size up to 48 bytes (that is, up to 6 Word64-s);
• but (unfortunataly) 4 extra words above that.

(This particular tradeoff was chosen so that pointer tagging still works on 64 bit architectures: there are 7 constructors of the data type.)

The Blob data type is useful if you want to store large amounts of small, serialized data. Some example use cases:

• small vectors of small nonnegative integers (for example: partitions, permutations, monomials)
• cryptographic hashes
• tables indexed by such things

the Blob type

data Blob

A Blob is a nonempty array of Word64-s. For arrays of length at most 6 (that is, at most 48 bytes), there is only a single machine word overhead in memory consumption. For larger arrays, there is 4 words of overhead.

Constructors

Blob1 !Word64

Blob2 !Word64 !Word64

Blob3 !Word64 !Word64 !Word64

Blob4 !Word64 !Word64 !Word64 !Word64

Blob5 !Word64 !Word64 !Word64 !Word64 !Word64

Blob6 !Word64 !Word64 !Word64 !Word64 !Word64 !Word64

BlobN !ByteArray#

Instances

Eq Blob

Defined in Data.Vector.Compact.Blob

Methods

(==) :: Blob -> Blob -> Bool

(/=) :: Blob -> Blob -> Bool

Show Blob

Defined in Data.Vector.Compact.Blob

Methods

showsPrec :: Int -> Blob -> ShowS

show :: Blob -> String

showList :: [Blob] -> ShowS

Bits Blob

Defined in Data.Vector.Compact.Blob

Methods

(.&.) :: Blob -> Blob -> Blob

(.|.) :: Blob -> Blob -> Blob

xor :: Blob -> Blob -> Blob

complement :: Blob -> Blob

shift :: Blob -> Int -> Blob

rotate :: Blob -> Int -> Blob

zeroBits :: Blob

bit :: Int -> Blob

setBit :: Blob -> Int -> Blob

clearBit :: Blob -> Int -> Blob

complementBit :: Blob -> Int -> Blob

testBit :: Blob -> Int -> Bool

bitSizeMaybe :: Blob -> Maybe Int

bitSize :: Blob -> Int

isSigned :: Blob -> Bool

shiftL :: Blob -> Int -> Blob

unsafeShiftL :: Blob -> Int -> Blob

shiftR :: Blob -> Int -> Blob

unsafeShiftR :: Blob -> Int -> Blob

rotateL :: Blob -> Int -> Blob

rotateR :: Blob -> Int -> Blob

popCount :: Blob -> Int

FiniteBits Blob

Defined in Data.Vector.Compact.Blob

Methods

finiteBitSize :: Blob -> Int

countLeadingZeros :: Blob -> Int

countTrailingZeros :: Blob -> Int

blobTag :: Blob -> Int

blobSizeInWords :: Blob -> Int

Number of Word64-s

blobSizeInBytes :: Blob -> Int

blobSizeInBits :: Blob -> Int

Conversion to/from lists

blobFromWordList :: [Word64] -> Blob

blobFromWordListN :: Int -> [Word64] -> Blob

blobToWordList :: Blob -> [Word64]

Conversion to/from ByteArray-s

blobFromByteArray :: ByteArray -> Blob

Note: we pad the input with zero bytes, assuming little-endian architecture.

blobToByteArray :: Blob -> ByteArray

eqBlob :: Blob -> Blob -> Bool

Hexadecimal

newtype Hex

Constructors

Hex Word64

Instances

Show Hex

Defined in Data.Vector.Compact.Blob

Methods

showsPrec :: Int -> Hex -> ShowS

show :: Hex -> String

showList :: [Hex] -> ShowS

hexWord64 :: Word64 -> String

hexWord64_ :: Word64 -> String

Peek

peekWord :: Blob -> Int -> Word64

peekByte :: Blob -> Int -> Word8

NOTE: We assume a little-endian architecture here. Though it seems that since GHC does not gives us direct access to the closure, it doesn't matter after all...

blobHead :: Blob -> Word64

extractSmallWord :: Integral a => Int -> Blob -> Int -> a

extractSmallWord n blob ofs extracts a small word of n bits starting from the ofs-th bit. This should satisfy

testBit (extractSmallWord n blob ofs) i == testBit blob (ofs+i)  

NOTE: we assume that n is at most the bits in Word, and that ofs+n is less than the size (in bits) of the blob.

extractSmallWord64 :: Int -> Blob -> Int -> Word64

extractSmallWord64_naive :: Int -> Blob -> Int -> Word64

An alternate implementation using testBit, for testing purposes only

change size

extendToSize :: Int -> Blob -> Blob

cutToSize :: Int -> Blob -> Blob

forceToSize :: Int -> Blob -> Blob

map and zipWith

mapBlob :: (Word64 -> Word64) -> Blob -> Blob

shortZipWith :: (Word64 -> Word64 -> Word64) -> Blob -> Blob -> Blob

longZipWith :: (Word64 -> Word64 -> Word64) -> Blob -> Blob -> Blob

unsafeZipWith :: (Word64 -> Word64 -> Word64) -> Blob -> Blob -> Blob