Lambda the Ultimate

Two interesting articles by Jaron Lanier on how protocols influence programming

SUN Interviev

If you look at the way we write software, the metaphor of the telegraph wire sending pulses like Morse code has profoundly influenced everything we do. For instance, a variable passed to a function is a simulation of a wire. If you send a message to an object, that's a simulation of a wire.

WHY GORDIAN SOFTWARE HAS CONVINCED ME TO BELIEVE IN THE REALITY OF CATS AND APPLES

If you model information theory on signals going down a wire, you simplify your task in that you only have one point being measured or modified at a time at each end. It's easier to talk about a single point in some ways, and in particular it's easier to come up with mathematical techniques to perform analytic tricks. At the same time, though, you pay by adding complexity at another level, since the only way to give meaning to a single point value in space is time. You end up with information structures spread out over time, which leads to a particular set of ideas about coding schemes in which the sender and receiver have agreed on a temporal syntactical layer in advance.

By comparing three versions of the memo (unsigned, but believed written by Irv Ziller) “Proposed Specifications for FORTRAN II for the 704″, dated August 28, September 25, and November 18, 1957, you can watch the design of the subroutine feature of FORTRAN II unfold.

Also: separate compilation.

As opposed to procedural abstraction, higher-order functions, etc. Nice answer from Patrick Logan (who was once a member of the LtU team but seems to have forgotten about us...)

I'm back... I had a great vacation (aside from being on my way to Toronto when this happened...) Now back to work ;-)

For interesting background on XQuery's development here's the full text of Udell's interview with Jonathan Robie.

Interpreting the Data: Parallel Analysis with Sawzall

"The query language, Sawzall, operates at about the level of a type-safe scripting language. For
problems that can be solved in Sawzall, the resulting code is much simpler and shorter – by a
factor of ten or more – than the corresponding C++ code in MapReduce."

I found this in my mail.

August 12, 2005

The Publisher and Editorial Board of Information and Computation are pleased to announce that for one year, effective immediately, online access to all journal issues back to 1995 will be available without charge. This includes unrestricted downloading of articles in pdf format. Journal articles may be obtained through the journal's web site http://theory.csail.mit.edu/~iandc or Elsevier's Sciencedirect at http://www.sciencedirect.com/science/journal/08905401

At the end of the year, the retrieval traffic during the open access period will be evaluated as future subscription policies are considered.

Albert R. Meyer, Editor-in-Chief, MIT Computer Science & AI Lab
Chris Leonard, Publishing Editor, Elsevier
Moshe Y. vardi, Associate Editor, Rice University

Those of a more theoretical bent will find lots of interesting articles there.

Not really about PLT, but this paper was mentioned on LtU before, and I believe it is a good reminder to people thinking that "research" means "useless".

Rigour is good for you and feasible: reflections on formal treatments of C and UDP sockets

Language designers give rigorous specifications of language syntax as a matter of course. [...] Rigorous definitions of type systems is less common [...] The situation for behavioural specification is even worse. [...] In the long term, we believe greater rigour is essential in the development of more robust software at all levels; there are many behaviourally subtle aspects of operating systems which could benefit from it, and for which the tools are now available.

Testimonials :-) :

"It would be difficult indeed to get more hard-nosedly pragmatic than C and sockets."
-- Paul Snively

From a comp.lang.scheme announcement (full text quoted below):

I'm happy to report that my publisher has agreed to make Concrete Abstractions available on the web for free, while continuing to sell the printed and bound edition. My co-authors and I hope this will allow a broader segment of the international community of schemers to take advantage of our work.

For those unfamiliar with it, I'm referring to "Concrete Abstractions: An Introduction to Computer Science Using Scheme," by Max Hailperin, Barbara Kaiser, and Karl Knight.

Follow the PDF files link from the main book page,
http://www.gustavus.edu/+max/concrete-abstractions.html

-Max Hailperin
Professor of Computer Science
Chair, Mathematics and Computer Science
Gustavus Adolphus College
800 W. College Ave.
St. Peter, MN 56082
USA

Quite a mouthful, I wonder if it would attract more people if it were titled "Interactive programming in Epigram" :-)

Guarded Induction and Weakly Final Coalgebras in Dependent Type Theory

In this article we are going to explore one approach to the representation of interactive programs in dependent type theory. The approach we take centres on the concept of "monadic IO" used in functional programming. We will see that in dependent type theory, besides non-dependent interactive programs in which the interface between the user and the real world is fixed, as in ordinary functional programming, there is a natural notion of state-dependent interactive programs, in which the interface changes over time.

Well, since language popularity seems to be overly emphasized in any discussion on PL, thought the following article on Have scripting languages peaked? would be of interest.

A recent study from Evans Data Corp... The study, published on Thursday, found that the number of people using PHP for development in Europe, Middle East and Africa fell by over 25% last year and that the number of developers who would not evaluate PHP for future product grew by almost 40 percent. Similarly, Perl and Python also saw significant drop-offs in usage and planned usage.

I think of Perl, PHP, Python and Ruby as mainstream programming languages, but it would seem that many consider them to be Strange or Exotic.