[Haskell-cafe] QuickCheck behaving strange

[Jason Dagit]

On Fri, Jul 24, 2009 at 11:29 AM, Felipe Lessa <felipe.lessa at gmail.com>wrote:

> On Fri, Jul 24, 2009 at 08:11:12PM +0200, Tobias Olausson wrote:
> > prop_schedule :: Ord t => [Interval a t] -> Bool
> > prop_schedule []        = True
> > prop_schedule [a]       = True
> > prop_schedule (x:y:ys)  = end x <= begin y && prop_schedule (y:ys)
> [..]
> > How come QuickCheck passes 100 tests of random lists? One would think
> that
> > at least one of the generated lists would be unsorted. It also passes
> > 1000 and even
> > 10000 tests.
>
> Probably it was defaulting to 'Interval () ()'.  Try to do


Cases like this make me feel as though the instance of Ord for () was  a
mistake.

Jason
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://www.haskell.org/pipermail/haskell-cafe/attachments/20090724/96f7beca/attachment.html