Possible records tweak

[John Rose]

On Apr 24, 2020, at 12:43 PM, Dan Smith <daniel.smith at oracle.com> wrote:
> 
>> On Apr 24, 2020, at 1:32 PM, Remi Forax <forax at univ-mlv.fr> wrote:
>> 
>>> (Which, in hindsight, might have been a good rule for _all_ constructors, if there was another way to initialize the fields.  Surely would have eliminated much verifier complexity.)
>>> 
>> accessing to the identity hashcode or the current class inside a constructor is valid (i believe) but those are a corner cases.
>> 
> 
> Ah, yes. This generalizes to calling methods that safely operate on an already-initialized superclass (typically instance methods of the superclass).
> 
> If we someday have abstract records or other forms of user-defined superclasses, it will be quite reasonable to call the superclass's instance methods from the subclass's constructor.
> 

So maybe `super` is DA but `this` is DU, just like in the code
before the super-constructor call.  (I’m abusing the terms DA/DU
like Brian is, and you call out, but they are close to correct.)