"Simon Peyton-Jones"
[replying to the GUI list]
I don't have a strong opinion myself -- I'm just advocating a little careful study, since Clean has a lot of experience.
Yes, definitely.
It might be worth asking Peter Aachten for his advice/ideas. Invite him to join the list?
True - that might be a good idea.
| * It integrates facilities for concurrent and distributed | programming (asynchronous communication via channels). I | still think, we can keep the GUI API and concurrency as | two orthogonal features. If you take these features out | and use IORefs instead of MVars, you are already quite | close to the model that we currently aim at.
Definitely agree to keep them separate. But I do think the GUI API should perhaps conceal whether it's using IORefs or MVars, since in a concurrent system one will certainly want to use the latter.
The goal for the Haskell GUI is to conceal this *and* to use neither of the two in the GUI library implementation. That's a property that I can't yet see how it can be realised with the Clean IO.
| * After this, the main difference that remains is the | representation of GUI components as a vanilla data type | instead of opaque handles that do not make the structure | of the components explicit in the types (like the TupLS | does). From the paper, it wasn't clear to me how useful | that is for the application programmer.
This is indeed the most significant feature. It has the merit that there is a data structure that acts as a description of the GUI, which has some conceptual clarity, for me anyway. Instead of building up a model in your head, there it is written down (you can presumably even print it out).
Not so good when the GUI shape is changing -- I wonder how Clean does that.
Another problem is extensibility, as the data declaration, eg, commits to the possible properties and supported callbacks of a widget. After having used GTK+, where all this is dynamically defined, this seems quite restrictive to me. But I completely agree with you. We need to take into account all the experience that is out there. (It's little enough anyway.) Cheers, Manuel