[Zope-dev] ComponentArchitecture thoughts

[Jim Fulton]

Dieter Maurer wrote:
> 
> Michel Pelletier writes:

(snip)

> I read the components proposal. I am not at all sure that
> this new model will become easier than the current one.
> 
> Now, I have to know:
> 
>   * which classes I need to mix in
>   * which magic members, I need to supply:
>     "security", "manage_options", "meta_type", "_properties", ...
>   * which magic functions, I need to call: "InitializeClass"
> 
> Later, I need to know:
> 
>   * which classes I need to mix in (fewer than now, agreed)
>   * which objects I need to cooperate with
>     maybe, how they are set up, configured
>   * which magic members, I need to supply:
>     "__implements__", ...
>   * ....
> 
> I am not yet happy.

Really, your second bullet got split into two 
bullets; everthing else is the same. I agree that there is 
the same "essential" complexity. I think that many would 
argue that components provide a cleaner separation of the 
complexity than mix-ins.  The component model envisions
more decomposition than we have now with mix-ins, for example, 
separating presentation from application logic. Many people
have bemoaned the intermixing of presentation logic and 
application logic in Zope today.

A really big win from the component model is that it will 
make it possible for people to extent or replace behavior in
other peoples content objects *without modifying the source*.

> Maybe, when I see how the cooperating
> objects are associated, set up, configured...

Yup.
 
Jim

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