Gearing up (again) for the next release: 2014.2.0.0

[Johan Tibell]

On Mon, Apr 7, 2014 at 4:18 PM, Nick Smallbone <nicsma at chalmers.se> wrote:

> On Monday 07 April, 2014 at 02:53 pm, Johan Tibell wrote:
> > > > Is StdGen so badly broken that it can't be fixed in a future version?
> > >
> > > The implementation of split is pretty broken. I suppose most people
> > > don't need split but, unfortunately, QuickCheck uses it heavily (the
> > > bind of the Gen monad splits the seed). I don't think anyone knows how
> > > to fix it, since there's no obvious reason why the current split should
> > > work at all!
> > >
> >
> > Basic question: is the type of split wrong or just the implementation?
>
> Just the implementation. However, another question (which I don't know
> the answer to) is whether the type of StdGen allows for a proper
> implementation of split.
>

It would be nice if we could just fix StdGen and thus not require a whole
new library. Will fixing StdGen make it even slower than it is today?

I believe the new generator used in QC uses some cartographic hash
function. I wonder if SipHash has been considered, as it's both fast and
has good randomness properties (but perhaps not for splitting).
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