[Moose-dev] Re: Class Extensions

Hi Guys, I looked a bit in more detail at the class extensions problem. Here I bring a bit more to the discussion table. I attach a Snaut screenshot of an analysis session of Hapax + Code Foo. (seems attachment is too big for the mailinglist so here's a link: http://www.inf.unisi.ch/phd/lungu/files/ClassExtensionsInMoose.png) The panel on the right is the detail of the 91 invocations abstracted in the high-level dependency between Hapax Development and Visual Works. To the right of every method which is extended in a different package thabn Base VisualWorks you can see that package. What you will see is that althoug most of those dependencies are defined in othe packages than VisualWorks Base they still are abstracted in the relationship between Hapax and VisualWorks base. You will see that there is a dependency between hapax and Number>>pythag: which methoid is defined in Hapax itself. The reason is the following. A method, even when it is an extension (isExtension is True) belongsTo a class. And the class, logically, belongs to the namespace where it was initially defined and is, logically, packaged in the package it was initially defined in. When I compute the high- level depedencies in softwarenaut i aggregate them from methods to classes and from there up along the namespace of package hierarchy. Since the extended methods are placed in their original classes, I end up with dependencies between the wrong packages. The high-level dependencies in softwarenaut are wrong because the model can not express the existence of class extensions.

I can see two solutions: - we introduce a FAMIXClassExtension as an explicit entity which is a class which has a reference to the extended class. maybe we can even introduce a new relationship which is Class Extension.

- we piggyback the class extensions on top of the classes in a similar way the metaclasses are implemented. In our example, for Collection we would define a Collection class in CodeFoo, SqueakExtensions, EyeSee and ech one of these would only contain the methods that it defines. I am interested if anybody else is interested in this. And I want to hear your opinions.

Cheers, Mircea. _______________________________________________ Moose-dev mailing list Moose-dev(a)iam.unibe.ch https://www.iam.unibe.ch/mailman/listinfo/moose-dev