| Portability | portable |
|---|---|
| Stability | experimental |
| Maintainer | jcpetruzza@gmail.com |
| Safe Haskell | None |
Data.Hash
Description
Combinators for building fast hashing functions.
Based on the BuzHash algorithm by Robert Uzgalis (see, e.g. "Hashing concepts and the Java programming language" at http://www.serve.net/buz/hash.adt/java.000.html)
- data Hash
- asWord64 :: Hash -> Word64
- hashWord8 :: Word8 -> Hash
- combine :: Hash -> Hash -> Hash
- hashWord16 :: Word16 -> Hash
- hashWord32 :: Word32 -> Hash
- hashWord64 :: Word64 -> Hash
- hashInt :: Int -> Hash
- hashStorable :: Storable a => a -> Hash
- hashFoldable :: (Foldable t, Hashable a) => t a -> Hash
- class Hashable a where
The Hash type
Basic combinators
combine :: Hash -> Hash -> Hash
h1 `combine` h2 combines hashes h1 and h2 into a new hash.
It is used to generate hash functions for complex types. For example:
hashPair :: (Hashable a, Hashable b) => (a,b) -> Hash hashPair (a,b) = hash a `combine` hash b
Derived combinators
hashWord16 :: Word16 -> Hash
hashWord32 :: Word32 -> Hash
hashWord64 :: Word64 -> Hash
hashStorable :: Storable a => a -> Hash
Observe that, unlike the other functions in this module,
hashStorable is machine-dependent (the computed hash depends
on endianness, etc.).
hashFoldable :: (Foldable t, Hashable a) => t a -> Hash
The Hashable class
class Hashable a where
Instances
| Hashable Bool | |
| Hashable Char | |
| Hashable Double | |
| Hashable Float | |
| Hashable Int | |
| Hashable Int8 | |
| Hashable Int16 | |
| Hashable Int32 | |
| Hashable Int64 | |
| Hashable Integer | |
| Hashable Word | |
| Hashable Word8 | |
| Hashable Word16 | |
| Hashable Word32 | |
| Hashable Word64 | |
| Hashable () | |
| Hashable a => Hashable [a] | |
| (Integral a, Hashable a) => Hashable (Ratio a) | |
| Hashable a => Hashable (Maybe a) | |
| (Hashable a, Hashable b) => Hashable (Either a b) | |
| (Hashable a, Hashable b) => Hashable (a, b) | |
| (Hashable a, Hashable b, Hashable c) => Hashable (a, b, c) | |
| (Hashable a, Hashable b, Hashable c, Hashable d) => Hashable (a, b, c, d) |