urbit-hob

commit 1120754e3b178bb17debe529a4f4da3372ba7d89
parent 18605a02cc87cef0e28257027d0d7dbc479cd2c3
Author: Jared Tobin <jared@jtobin.io>
Date:   Fri,  6 Sep 2019 04:56:30 -0230

muk: add module

'Muk' implements a particular version of a simple murmur3 hash.

Diffstat:
A
src/Muk.hs
 | 
18
++++++++++++++++++

1 file changed, 18 insertions(+), 0 deletions(-)
diff --git a/src/Muk.hs b/src/Muk.hs
@@ -0,0 +1,18 @@
+{-# OPTIONS_GHC -Wall #-}
+
+module Muk (
+    muk
+  ) where
+
+import Data.Bits
+import qualified Data.ByteString.Char8 as B8
+import Data.Char
+import Data.Word (Word32)
+import qualified Data.Hash.Murmur as M
+
+muk :: Word32 -> Word32 -> Word32
+muk syd key = M.murmur3 syd kee where
+  kee = chr lo `B8.cons` chr hi `B8.cons` mempty
+  lo  = fromIntegral (key .&. 0xFF)
+  hi  = fromIntegral (key .&. 0xFF00 `div` 256)
+