On Fri, Mar 6, 2009 at 9:20 AM, Andreas Raab <andreas.raab at gmx.de> wrote:
> Hi Alain -
>
> Alain Plantec wrote:
>>
>> With Pharo approach, your code depends on a unique small hierarchy of
>> classes exactly as it can depend on Collection one.
>
> To me there is a big difference: From my perspective all preferences code is
> UI code. Why? Because at the system level we use class variables and
> messages, not preferences. At the system level if you want to broadcast an
> event you use announcements or some other event system.
>
> The sole purposes of preferences is to expose certain system variables to
> the end-user. Consequently, preferences are part of the UI layer.

Currently traveling, so only a brief remark ;-)

I have to disagree with this assumption. For me preferences are also a
way to control non UI and also non end user settings in a system. A
simple example (maybe not even a good one) would be settings for a
server environment that I need to keep outside the image so I can drop
in a deployment image on every server. You don't want to have to run
special initialize do-its on a headless server image.

I also have a deep mistrust against all automagical gathering of
things (e.g via pragmas) as you loose control over the mechanism. I
like explicit registration of e.g. preferences, but that might be a
matter of style.

Michael