-- Hoogle documentation, generated by Haddock
-- See Hoogle, http://www.haskell.org/hoogle/


-- | Provide a simple consistent hashing mechanism
--   
--   Provide a simple consistent hashing mechanism
@package Data-Hash-Consistent
@version 0.1.1


-- | Data.Hash.Consistent
--   
--   A consistent hash is a technique to manage the fair distribution of
--   cacheable entities among hosts. Each host identifier has its crc32
--   hash calculated and stored in a Vector along with its canonical host
--   name. The host identifier may be differentiated from its canonical
--   host name by a multiplying factor, in our case a simple integer
--   appeneded to the hostname to provide it with a number of entries in
--   the consistent hash, all evenly distributed.
--   
--   This technique is explained in these links:
--   
--   http:<i></i>en.wikipedia.org<i>wiki</i>Consistent_hashing
--   
--   
--   http:<i></i>www.tomkleinpeter.com<i>2008</i>03<i>17</i>programmers-toolbox-part-3-consistent-hashing/
--   
--   Here is a small program illustrating its use:
--   
--   <pre>
--   module Main where
--     import qualified Data.Hash.Consistent as CH
--   
--   main = do
--       let hosts  = [<a>hi.example.net</a>,<a>bar.example.net</a>,<a>foo.example.net</a>] :: [CH.Host]
--       let n = 2 :: Int
--       let ch = CH.new
--       print $ show $ ch
--       ch &lt;- return $ CH.add hosts n ch
--       print $ show $ ch  
--       let fh = [head hosts] :: [CH.Host]
--       let hh_fh = CH.hashHosts fh n
--       print hh_fh
--       ch &lt;- return $ CH.del fh n ch
--       print $ show $ ch  
--       let i = 770931073
--       let tgt = CH.targetHost i ch 
--       print tgt
--       return ()
--   </pre>
--   
--   License info:
--   
--   The license is a simple BSD3-style license available here:
--   https:<i></i>www.b7j0c.org<i>stuff</i>license.txt
module Data.Hash.Consistent
textCrc32 :: String -> Hash
search :: Hash -> ConsistentHash -> Int
add :: [Host] -> Int -> ConsistentHash -> ConsistentHash
del :: [Host] -> Int -> ConsistentHash -> ConsistentHash
new :: ConsistentHash
targetHost :: Hash -> ConsistentHash -> HashHost
hashHosts :: [Host] -> Int -> ConsistentHash
type Host = String
type Hash = Word32
type HashHost = (Hash, Host)
type ConsistentHash = Vector HashHost