[cap-talk] "Composite", was "Same" key

[Bill Frantz]

I have real problems with the term "composite" meaning a multi-faceted
state bundle.  Much of the problem comes from the fact that it violates
David's statement (slightly rewritten):

>we should not be basing our terminology on the viewpoint of people who
>do try to understand concepts in terms of particular implementations.

"Composite" only makes sense in systems which do not support method
availability sub-setting as part of the reference, and even worse, gives
a seriously wrong impression in systems which do support such
sub-setting.  (CapOSes and language systems with fat pointers allow such
sub-setting.  Vtable (and other) systems do not.)

The terminology I like better is multi-faceted object, or just object,
but I am open to other suggestions.  I might even tolerate
"multi-faceted state bundle", but I suspect most would not.  Note that
in systems with method availability sub-setting in references, the
(single) object has all the methods that are described by a union of all
its facet's methods, so we do maintain the definition of object as state
and the methods that act upon it.

Building a composite of many objects to achieve this goal is an
implementation work-around for systems that do not have this level of
expressiveness natively, and might not be necessary in systems where
references of an interface type can not be cast to the implementing
class.  In these systems, we might be better off calling the front-end
objects, "method availability sub-setting" objects.

Cheers - Bill

-----------------------------------------------------------------------
Bill Frantz        | I like the farmers' market   | Periwinkle 
(408)356-8506      | because I can get fruits and | 16345 Englewood Ave
www.pwpconsult.com | vegetables without stickers. | Los Gatos, CA 95032