control orientations and compound documents

5.6: adda/oop/the orientation space:
--. this article explores how menus
should work in compound documents,
and how they relate to oop (obj'orientation) .
5.6: 5.31: equivalent terminology systems:
(user -- client
, app -- server
, menu -- type
, document -- object
).
5.6: 5.31: control orientations:
# open structure:
. text is an example of an open datatype:
(it's an array of symbols encoded with ascii);
any operation can be applied to this type
as long as it results in the same structure .
# open interface:
. only a particular set of operations can be applied;
but the menu is a public standard;
so, you can know ahead of time
whether something is on the menu or not .
# proprietary:
. neither the document structure nor the menus
are public standards;
so, only a particular app controls the object .
5.4: compound documents:
. support of compound documents means that
selecting multiple objects would result in
a menu consisting of the intersection of
the set of object`menus; 5.6:
every object can tell you the menu it supports
without having to adopt an interface .
5.31:
. if mac.finder were a compound document,
file`info would link not only to the owning'app
but also to that app's select-all menu .