(j3.2006) Is 7.2.1.2p1(1) necessary?

[Van Snyder]

On Fri, 2015-03-13 at 10:24 +0900, Malcolm Cohen wrote:
> >Type safety isn't compromised by what I propose.  It just means that you
> >must either
> >  (1) prove a theorem that the dynamic types are the same,
> 
> Ah, so no-one ever gets subscript errors by the same reasoning.
> 
> >> Could we design a type-safe assignment for this case?  Yes we could.  Some 
> >> new
> >> syntax would be needed, but it's certainly not impossible to do.
> >
> >We already have a type-safe assignment for this case.  It's SELECT TYPE.
> 
> No it absolutely is not.  SELECT TYPE is not an assignment, it's type selection.

Right, but once you reach the block in a TYPE IS, and do an assignment,
the assignment is type safe.

> Cheers,