Thursday 27 November 2008

Alex Summers

Congratulations to Alex Summers whose PhD I examined with Hugo Herbelin at Imperial yesterday. Hugo and I (well, okay, mainly me) had lots of questions for Alex but he did a great job in answering them. His thesis addresses the question "what is the computational content of classical logic?" He looks at both sequent calculus and natural deduction formulations.

He has two very striking results. The first considers the question of adding ML-style polymorphism to classical logic. There are some old results from Harper et al. showing that this is non-trivial (i.e. unsound) but Alex shows that a proof theoretic approach can lead to sound answer. This is a very interesting result (we probably discussed this one result for an hour in the viva!).

The second striking result concerns his variant of the lambda-mu calculus. He derives a set of reduction rules that are able to simulate control operators with prompts. Until I read this I wouldn't have thought it possible. His calculus - the nu-lambda-mu calculus - is very elegant, and tidies up some of the loose ends that I tried to hide under the carpet when I was devising an operational theory for languages with control operators back in the nineties! If I had more time I'd probably go back to my old MFCS paper and see if the results would be improved by using a better calculus.

Anyway, Alex has some small changes to make but I'd expect his final version to be available soon. I recommend it to you!

Wednesday 19 November 2008

Ona

Mateja's in the press again. I'm married to a media superstar :-)

Thursday 13 November 2008

Windows 7

Today, Austin gave us a trip report from PDC. As you may know, Microsoft demoed many things at PDC, including the successor to Vista, code-named Windows 7. Actually Austin gave the talk from a machine running Windows 7. I have to say that Windows 7 looks like a significant improvement on Vista. Aside from the eye candy (which is good too) it does seem that Windows 7 is both faster and smaller (it can target netbooks!). I'm really looking forward to playing with a beta!

[There's stuff on the web if you want to take a look. Here's some material on ZDNet. ]

Tuesday 11 November 2008

Code

As I'm writing some code at the moment, it's nice to see that I'm not the only one who forgets to fix quick work-arounds!

Friday 7 November 2008

Jazz Radiohead

Today The Guadian had an interesting article where they gave five jazz artists the Radiohead song "Nude" and asked them to make a recording of it. There are some interesting results. You can hear them here.

[If you don't have it already, the latest Radiohead album "In Rainbows" is, in my opinion, a work of genuis.]

Tuesday 4 November 2008

Software services + DSU

I just read this note by Gilad Bracha. It's very nice (albeit a little light on concrete details). Gilad's aim is to consider an OO platform for software services, paying particular attention to the programming language perspective.

I was pleasantly surprised to see Gilad talking about dynamic software updating - indeed it's core to his proposal.

I had thought that our UpgradeJ paper would be the last thing I did on DSU (or rather the journal version - still in progress - would be). Maybe it was more prescient than we realized :-)

Check out Gilad's paper for yourself!