Musings about modularity and programming in the large

itsme213 itsme213 at hotmail.com
Thu Jan 24 19:50:03 UTC 2008


"Andreas Raab" <andreas.raab at gmx.de> wrote

>> It is about metaclasses not being "special" or hidden or singletons, but 
>> being just as user-accessible, definable, instantiable, and extensible as 
>> any other object (and class). It is a much simpler meta-structure than 
>> Smalltalk-80.
>
> I'll have to admit I never liked this model too much. One of the killer 
> features of the Smalltalk-80 model is that it allows you to add features 
> to the meta class easily (by just clicking on the meta-tab in the browser) 
> be that class instance variables, instances creation, utility, example, or 
> test methods.

I agree that is extremely convenient. But could it be thought of as good 
tool / browser design? Even on Cointe's model, could a tool that knows it is 
editing a class make it just as painless to
  1. select a metaclass
  2. create a metaclass on the fly
  3. do 1 & 2 with on-the-fly customizations to ((meta)class)instVars, 
methods...

(Ruby's instance-level customizations do things similar to 1 & 2; our 
instances would be classes).

I can imagine (newbie alert :-), a similar "class" tab with similar 
convenient behaviors. Plus the added benefit, specially for those interested 
in meta-modeling and DSLs, of all full access to any levels of "metaclass" 
definitions.

Sophie






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