One of the nicer features of QKS SmalltalkAgents, which could serve as a model for work in Squeak, was the Namespace class. This class allowed for the creation of isolated classes and even the overriding of methods in basic classes (like Object!) without causing disastrous side effects in the overall system. Only projects defined in a given Namespace would see the classes or methods defined in the Namespace. I am not sure whether the mechanism was general enough to permit moving an existing class into a different part of the class hierarchy, but I would not be surprised if that were part of the deal. The overall goal, I think, was to create compatibility zones for ParcPlace, IBM and even Digitalk fileins - I am not sure how much of this was ever implemented. There was also a facility for constructing loadable/unloadable bytecode modules, and for shipping standalone applications by pruning off every class other than those needed by the app and compiling the bytecodes into native machine code (the virtual machine would therefore not have to be shipped with the app).

Hmm. This is at least the second time I mentioned this Smalltalk implementation in this group. The reason is that it was the only commercial Smalltalk I ever bought, not that I have any particular bias one way or the other. At the time, it was the only product that 1) Ran on my Mac; 2) Had a complete set of classes (Squeak didn't exist; gnu had incomplete GUI support); 3) I could afford (I bought it cheap at Macworld, but free would have been better). All in all, though, it had a lot of good features I have never seen anywhere else. I don't even know if it still exists.

Ed

Les Tyrrell wrote:

There are a number of interested parties- my own approach, evolving as we speak, is partially described at:

http://www.canis.uiuc.edu/~tyrrell/Squeak/Personal/Oasis/index.html

The description is actually very sparse, I really need to update this. Oasis, like most of what I do, is written for VisualWorks. However, it is not UI-dependent so I don't anticipate much difficulty in porting it to Squeak. I'm close to finishing up one of the analysis tools in Oasis, so perhaps I can get something decent written about it in the near future- the current description of Oasis is very inadequate. Basically, given some arbitrarily huge chunk of code, Oasis tears it apart and builds a number of useful analytical models that I can then browse ( but without a UI at this time ).