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Google Tech Talk: Phil Gosset discusses parametric polymorphism and girard-reynolds isomorphism

http://video.google.com/videoplay?docid=-4851250372422374791&q=user%3A%22Google+engEDU%22&hl=en

Enjoy.

By Chris Perkins at 2007-04-25 04:28 | LtU Forum | 6 comments | other blogs | 7838 reads

Arc in action (a.k.a. it's aliiiiive!)

Recent discussion of what software LtU is running, and what languages it relies on, reminded me of Paul Graham's language, Arc. Despite many rumors of its death, Arc's seed finally sprouted in February, when Paul's startup incubator, Y Combinator, launched a reddit-like social news site for startups, Y Combinator Startup News. In the launch announcement, it was mentioned that the site is built with Arc:

And of course another reason we made this site is that last summer we wrote the first reasonably efficient implementation of Arc, and we were looking for something to build with it.

This month, a new version of the news site was released, based on a new version of of Arc with the innards redone by Robert Morris to reduce consing[*], resulting in a 2-3x speedup.

Arc still isn't available to the public, but painstaking NSA-class analysis of the related threads, Why we made this site and New, much faster version of News.YC reveals that Arc code in the current implementation compiles, mainly by macroexpansion, to MzScheme code. The news site's web server is also written in Arc.

There's not much more news than that, which is why I'm not posting this as a front-page story.

[*] Perhaps this could be considered an example of the hot new trend for zero-cons programming?

By Anton van Straaten at 2007-04-25 15:51 | LtU Forum | 38 comments | other blogs | 28484 reads