common types + type modifiers

[Simen kjaeraas]

Michel Fortin <michel.fortin at michelf.com> wrote:

>> unless it's acceptable to just make the mutability const. which would  
>> give:
>>          cs            m           cs
>>         cs            c           cs
>>         ms            m           cs
>>         ms            c           cs
>
> No, that doesn't work. There is no common type between shared and  
> non-shared.

It's also worth add why this is so: shared guarantees that reads and
writes do not overlap. This means all references to an instance must
type it as either shared or non-shared.


-- 
Simen