nominolo / murmur-hash

[New maintainer needed] MurmurHash2 implementation in Haskell

murmur-hash

New maintainer needed. Let me know if you're interested.

A simple, Haskell-only implementation of MurmurHash2.

Two variants are provided: 32 bit and 64 bits. We do not simply use the machine word size since the bit width of the hash determines the collision probability which should stay under user control.

Example Usage

Generating hashes:

$ import Data.Digest.Murmur32
$ hash32 "foo"             ==> Hash32 0xd2d0a99a
$ hash32 "foa"             ==> Hash32 0x7d544e71
$ hash32WithSeed 42 "foo"  ==> Hash32 0x7a69563b

Custom instances:

data Foo a = Foo a | Bar String

instance Hashable32 a => Hashable32 (Foo a) where
  hash32Add (Bar s) = hash32AddInt 1 `combine` hash32Add s
  hash32Add (Foo a) = hash32AddInt 2 `combine` hash32Add a

murmur-hash's Issues

murmur-hash large files

I'm trying to murmur-hash a large file, but I get:

Stack space overflow: current size 8388608 bytes.
Use `+RTS -Ksize -RTS' to increase it.

My code is at https://github.com/bneijt/dirsum/blob/master/src/Hashing.hs

Small files work, larger files don't. How do I hash large files?

Add benchmarks with 'hashable' and 'blake2b'

It's good to have performance comparison with other hashing libraries because murmur is supposed to be the fastest one.

Consider using hashabler to support hashing arbitrary types?

Would you be interested in merging changes that permitted hashing of arbitrary Hashable types from my hashabler package? The resulting hash functions would look more or less the same. This would allow hashing of many more instances, and take care of cross-platform consistency for you, etc.

I'm not sure when I'd be able to get to this, but I wanted to float the idea first. Let me know if you're interested and would like more details about what that might look like.

Doesn't build with ghc-7.2.1-rc1

Yet again base >= 3.0 && < 4.4 is too restrictive for GHC 7.2.x (see also issue #1, when this happened for GHC 7.0.x)

Please relax the constraint, thanks!

Missing support for GHC 8.0.1

Using GHC 8.0.1-rc4, I needed the allow-newer=baseoption for installing murmur-hash 0.1.0.8.

Could you relax the upper bound version for base and release on Hackage a new version, please.

Relax `bytestring` to `<= 0.12`

Relax bytestring to <= 0.12.
This can be done in a hackage revision at https://hackage.haskell.org/package/murmur-hash/maintain, no need for uploading a new version.

murmur-hash doesn't build on ghc 7

Hi,

The base dependency in murmur-hash.cabal is too restrictive, and murmur-hash doesn't build on GHC 7. Could you please fix this? Thanks