Gearing up (again) for the next release: 2014.2.0.0

Nick Smallbone nicsma at
Mon Mar 31 18:58:30 UTC 2014

Hi Mark,

On Monday 31 March, 2014 at 11:15 am, Mark Lentczner wrote:
> On Mon, Mar 31, 2014 at 10:32 AM, Nick Smallbone <nicsma at> wrote:
> > One complication is that we switched to a different random number
> > generator because of some flaws with the one in System.Random.
> > So we would also need to pull in the tf-random package
> > (
> >
> This is unfortunate. That package doesn't look like a likely candidate for
> the platform: It is new, and the API looks like it has been in rapid,
> non-stable development for the last month.

Yes, I understand this objection. Then perhaps we should hold back on
it for now and see how we stand the next time around.

> Is is possible that you can make QC work with standard random package, and
> only use tf-random as an option? Is there something seriously flawed in
> random that should be fixed there?

I would rather not switch back to StdGen. We have stumbled into
situations in the past where we can't falsify a property just because
StdGen can't come up with the right random values - while (thankfully)
extremely rare, it makes me uncomfortable that it happens at all.
This mostly happens when generating random functions.


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