Richard Eisenberg <[email protected]> writes: > I had another thought on my drive home: why do we need to sort out > Constraint v Type for 8.2? I have the patch, and it's essentially all > set. But it weakens equality in a way that's troublesome for D2038 and > introduces heterogeneous axioms, which are strange, ill-understood > beasts. And I don't think we need it. > > On the other hand, D2038 is essential for the new Typeable, because > it's the only way we can give (->) a proper kind. > Snipped well-considered plan for proceeding.
> This route seems, to me, far preferable to monkeying around with roles > and such in ways that we have no assurances are sound. (Remember, > roles are there to keep the type system safe and sound. They were not > added simply to annoy everyone, though they accomplish that goal quite > nicely.) > :) > What do we think? It's not ideal, but I think it's the best of > suboptimal alternatives. And it's no worse than 8.0 w.r.t. Constraint > v Type. > This sounds quite reasonable to me. I will need to fix up the remaining issues in D2038 surrounding Constraint, but I think this shouldn't be so difficult. The only reason I haven't tried already was my belief that Constraint/Type would be resolved soon. I'll try to push another version of D2038 tonight. Cheers, - Ben
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