FTfJP 07 (at ECOOP)

The second day at ECOOP was taken up with the FTfJP workshop. There were lots of interesting talks and I'll only blog about a few of them. I spent all day there, but I really should have been elsewhere at 2 to listen to Gilad Bracha's talk at DyLA, which lots of people were talking about and sounded pretty interesting from chatting to Gilad. The talk was (apparently, I still need to read the paper) about Gilad's new language which he is developing at Cadence. All I really know is that it is dynamically types and involves some kind of virtual class construct, of which I am a big fan!

So onto the talks, the accompanying papers can be found at the FTfJP link above:

First up was a good looking lad talking about some wildcards rubbish. I thought the talk went pretty well and I got interested questions, so at least some people were following and were interested. I also got some useful feedback afterwards, so that is always nice.

Vincent Cremet or Philippe Altherr - Adding Type Constructor Polymorphism to Java - This was a nice idea to make Java generics more expressive by allowing formal type parameters to be parameterised, thus having the power of full type constructors. You get quite a lot of extra expressivity for no extra syntactic constructs and very little syntactic overhead, which is similar to what already exists, so its a winner all round really. However, it does make the declaration of generic classes even more complex and ugly, so I can't see it being in Java 7.

Chieri Saito - The Essence of Lightweight Family Polymorphism - This was really interesting to me, particularly as I think the lightweight family polymorphism idea is great. The idea here was to attempt to translate lightweight family polymorphism programs into Java with generics to discover how much of their system is syntactic sugar and how much is actually new. They found that most could be translated away, but they needed an extra construct, to give a more specialised type to 'this', in order to translate the complete language. This was formally done by translating .FJ to FGJ.

Elena Giachino - Seperating Type, Behaviour and State to Acheive Very Fine-Grained Reuse - this is another neat idea, this takes the ideas behind traits a step further and further breaks up classes, so there are seperate constructs for behaviour, state, object creation and types. This seems to break things down to the bottom level and means reuse levels are really high. This is very elegant and interesting, however, there must be a tradeoff in the real world with practicality, and having so many little 'micro-classes' kicking around must get to be hard work, I think this even came across in the talk as the conceptual divisions were pretty porous and so in the examples bits of state would appear in the behaviour modules and so forth. Still a great idea and intellectually very interesting.