Re: But is it Object-Oriented?

Isaac Gouy wrote:

>>>>BTW, Java is specified roughly in the same way, and uses the name 
>>>>"compilation units" for "modules".
>>>>        
>>>>
>>>And the significant difference is, of course, that Java doesn't use
>>>a "compilation unit" for encapsulation - Java uses types (classes
>>>and interfaces) for encapsulation. 
>>>
>>>      
>>>
>>Right, but since you are supposed to have only one top-level class
>>per compilation unit, the difference is somewhat blur.
>>    
>>
>
>Which means that the top-level class provides a syntactic boundary for
>the "compilation unit" - no such boundary in Nice.
>  
>
Yes.

We could add a construct for isolating a unit, and then either force 
each "file" to contain units (a la Java, seems redundant) or make each 
file an implicit module, but allow nested modules (a la ocaml).

>Let's see if we can be a little more concrete: in the wiki example 
>
>http://nice.sourceforge.net/cgi-bin/twiki/view/Doc/HelloSwtUserInterfaceExample
>
>It wouldn't be unlikely that we'd decide to subclass HelloGoodbye and
>override helloButtonSelected. This (helloButtonSelected) is a method
>that seems like it should be private, it's only useful in this context
>or maybe when we subclass - we'd probably make it protected in Java, 
>
>What to do in Nice?
>  
>
This seems to me a different issue, which is how to define 'protected' 
in Nice. One possibility could be that a protected method can be 
overriden from anywhere there are new specializations for the parameters 
available (a generalization of "in subclasses", which actually coincides 
for mono-methods), but cannot be called publicly (alternatively, can be 
called when it can be overriden). The alternative more closely matches 
Java, but the I often felt the need for "overridable but not callable" 
methods, so that could be interesting. In this case, it seems that it 
would make sense: you can specialize the behaviour when the button is 
clicked, but the method can only be called when a click event is generated.

Daniel



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