Thoughts on Gengtype and Single Inheritance

[Lawrence Crowl]

On 8/30/12, Gabriel Dos Reis <gdr@integrable-solutions.net> wrote:
> On Aug 30, 2012 Richard Henderson <rth@redhat.com> wrote:
> > On 08/27/2012 11:58 AM, Lawrence Crowl wrote:
> > > > > I wonder if the second discriminator support is easily
> > > > > generalizable to enabling any derived class being a root
> > > > > class on it own with its own subtree? If I understand
> > > > > correctly, the GTY syntax would be the same.
> > >
> > > If I understand correctly, you are suggesting multiple
> > > inheritance via enums.  I think it is possible, but I think
> > > the tag syntax would need to be changed to more directly
> > > associate the tag with the variable.
> >
> > I understood Laurynas to be suggesting not multiple inheritance,
> > but composition?
>
> The coding convention recommends avoiding multiple inheritance, but
> it did not ban it altogether.  I would be unfortunate that gengtype
> takes the step of banning it -- by effectively not supporting it.

The present implementation need is for single inheritance.  It would
be reasonable to plan for eventual support of multiple inheritance.
Do you have a suggestion for syntax to that end?

-- 
Lawrence Crowl