[PRL] POPL NOTES

[Sam TH]

On Tue, 18 Jan 2005 19:02:38 -0500, Johan Ovlinger <johan at ccs.neu.edu> wrote:
> > Virtual types: when you specialize subject, then you need to
> > specialize observer and event classes.  Violates behavioral
> > subtyping.
> >
> > KB's solution:  "mutually recursive groups"; use @ThisTG (exactly this type
> > group) to get comon covariant specialization.
> 
> Huh.
> 
> I'm surprised Erik Ernst / Klaus Ostermann didn't chime it at this
> point with a pointer to family polymorphism.

I think Bruce referenced their work explicitly.

-- 
sam th
samth at ccs.neu.edu