General talk about software patterns

[Al Boldi <a1426z AT gawab.com>]

Ralph Johnson wrote:
> Messaging Design Pattern 
> <dsheppard2k AT yahoo.com>
>  wrote:
> > The MDP papers are mainly geared towards the messaging concept based on a
> > realistic model.
> > I tend to place a lot of emphasis on the concept, abstraction and
> > realistic model. In my opinion, concept and interface are the main aspects
> > in order to achieve a successful implementation.
>
> I think your papers are not working.  Most people don't get the idea after
> reading them.   I think the problem
> is that you focus too much on this "realistic model".  The problem is that
> the realistic model can be
> interpreted in many ways, and MDP is only one of them.   Smalltalk
> programmers ALL use the same model.
> When I read your paper for the first time, I thought you were just talking
> about the classic OO model that
> we Smalltalkers have loved for 30 years.  You need to try to write things
> that cannot be misinterpreted.
> I think you are trying to avoid having people say "You are crazy!" right
> away, but if they properly understand
> what you are saying (and they have not seen this pattern used properly
> before) then they will say it.
> They ought to say it.  When people say "You are crazy!" then you know that
> they are starting to understand.
> Your job is to convince them that you are not crazy, that this is in fact
> often a valuable pattern.

Maybe I am missing something, but the MDP is definitely not a crazy idea.  
And 
yes, the MDP concept has been around for a long time, which should make it 
eligible for a design pattern.

The only problem I see here is that the MDP is a complex pattern.

Complex patterns as opposed to simple patterns, like ITERATOR and VISITOR, 
need to be decomposed into their respective simple patterns, to aid the 
developer in the implementation of the complex pattern.  It is this 
decomposition of the complex pattern that in turn should clarify many of the 
possible interpretations of the complex pattern.

So, for the case of the MDP, has this decomposition be performed?


Thanks!

--
Al