a new contract for reference types
peter.levart at gmail.com
Wed May 8 06:37:18 UTC 2019
On 5/2/19 12:29 AM, John Rose wrote:
> Regarding subtyping, I don't see (from these considerations)
> a firm reason to declare that V? is a super of V. The value
> set of V?*might* have one more point than that of V,
> or it*might not*. The reason we are doing V? is not the
> value set, but the whole contract, which includes the
> value set as an obvious, but ultimately non-determinative part.
Just one observation...
If inline class V was declared to support a "kind" of null (default,
sentinel) value by itself, then how such value would be denoted?
Is this a way?
V v = null;
If this was possible, then what would be the distinction between the
following two then?
V? vInd1 = null;
V? vInd2 = v;
Would vInd1 and vInd2 represent the same "null" value?
More information about the valhalla-spec-observers