Darren New <dne### [at] sanrrcom> wrote:
> >   I may be unusually dumb today, but I did not understand anything of that.

> I'm saying that if an object's lifetime is controlled by code outside 
> the object, then you have lost the modularity. Objects are no longer 
> independent reusable items.

  Well, that's a question of good modular design. I still don't understand
how it is related to whether a specific language is OO or not.

> Not at all. I'm making a point about languages that don't do memory 
> management aren't OO, exactly because then you no longer have modules.

  So are you saying C++ is not an OO language because it doesn't have
an automatic memory management system?

> >   Modules are an essential tool for encapsulation and abstraction.
> > You simply can't have objects if you don't have modules.

> However, the term "module" is so vague as to be useless. Is UCSD Pascal 
> "modular"? How about machine code? What if each object is in a separate 
> process, so the only communication between them really is "message 
> passing", yet each object is written in a language without modules?

  Defining a module is rather simple: A module is an encapsulated entity
which has a state defined by its member attributes and a public
interface to handle that state.

  In a good OO language the state of the module can (or even better, must)
be private to the module (ie. not accessible from outside the module),
and can be handled only through the public interface.

  A module might not have a state at all (if it doesn't have any
member attributes) but it can have if needed.

  You can have instances of modules and each instance can have its own
state (independent of the other instances). These instances are called
objects.

-- 
#macro M(A,N,D,L)plane{-z,-9pigment{mandel L*9translate N color_map{[0rgb x]
[1rgb 9]}scale<D,D*3D>*1e3}rotate y*A*8}#end M(-3<1.206434.28623>70,7)M(
-1<.7438.1795>1,20)M(1<.77595.13699>30,20)M(3<.75923.07145>80,99)// - Warp -

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