[cap-talk] "ambient authority" on wiki.erights.org

[Karp, Alan H]

David Wagner wrote:
> >I have been treating a static, immutable, authority carrying variable as
> >part of every object's creation state, not different in any essential
> >way from an argument passed to its constructor.
> 
> It seems different to me, in some essential ways:
> 
>  * With a global authority-carrying variable, you can't prevent some
>    objects from receiving this authority.  If it is passed as an
>    explicit argument to the constructor, you can.
> 
>  * With a global variable, the default is to make this authority
>    available to all code.  If it is passed as an explicit constructor
>    arg, then the default is to not provide this authority.
> 
> These differences seem important.

I agree completely.  I should have added "for the purpose of defining ambient authority" to my statement.  MarkM said it better than I did.  It's useful to distinguish ambient and undeniable (implicit).

________________________
Alan Karp
Principal Scientist
Virus Safe Computing Initiative
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