RE: reply to `I hate this error'

[Simon Peyton-Jones]

> > Intervals.hs:460:
> >    Illegal constaint `Ord (s e)' in instance context
> >        (Instance contexts must constrain only type variables)
> 
> 
> Is not this due to omitting
> 
>    -optC-fallow-undecidable-instances  
> -optC-fallow-overlapping-instances

That's right. It's the undecidable instances one in fact.
Sorry about the -optC; we need to update the driver to recognise it

Simon