Data.HashTable performance

Johan Tibell johan.tibell at
Wed Apr 6 10:23:32 CEST 2011

Hi Frank,

You can try out the new Data.HashMap data structure by running

    cabal install unordered-containers

from a shell and then

    import qualified Data.HashMap.Strict as Map

in your Haskell program.

It's currently the fastest *persistent* (i.e. purely functional)
Haskell map implementation I know of. (Full disclosure: I wrote it.)

The Git repo is here:

If you want a fast mutable hash table Gregory Collins (CCed) have been
working on a few implementations that beat Data.Hashtable by a large
margin. I don't know if they're ready for general use yet (i.e. they
haven't been released on Hackage yet).


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