Re: Dynamic Variant Record Creation

[Adam Beneschan <adam@irvine.com>]

On Mar 16, 1:31 pm, Robert A Duff <bobd...@shell01.TheWorld.com>
wrote:

> On the other hand, I can imagine some rule based on subtypes,
> where you don't know the discriminant statically, but you know
> statically that it's in a particular subtype that all shares
> the same variant.

Yes, that was discussed in AC-17.  One issue that I don't think was
discussed there, however, was that the same discriminant can govern
more than one variant part, in the case of nested variants, and then
you have issues with discriminated type extensions where an ancestor
type may be a discriminant type constrained by the derived type's
discriminant.  Making sure the rules work in all cases is likely to be
a pain.

                                        -- Adam