RefObject and ValObject

[John Rose]

The word "reference" is available and fits the bill.
"nullable reference type"

> On Apr 15, 2019, at 2:23 PM, Brian Goetz <brian.goetz at oracle.com> wrote:
> 
>> V <: V? by value set inclusion; V? is the type obtained by adjoining `null` to the value set of V.  
> 
> Looking for.a better name for this.  :”Nullable value types” is a terrible name, so I don’t want to say that.  (Too confusing with null-default value types.). They could properly be define as “null-adjoined value types”, but that’s not helpful if you don’t know what an adjunction is.  Similarly for “nullable projection”.  
> 
> But the basic idea is that V? is the denotation of the union type of V | Null.  
>