[Haskell-cafe] ideas for extending 'tensor'

Hi Nicola, I was very excited to see your type-safe tensor package. Are the sources available somewhere for contributing? I'd be interested in trying to extend it to use unboxed vectors, or perhaps even repa or yarr. Are there any future plans like that? Also it'd be interesting to add the distinction between covariant and contravariant indices, although this would be most likely a major change. Or perhaps it'd be possible to add it just as some kind of a wrapper. All the best, Petr