Fun

Solving a Sudoku with one SQL-statement

Doing strange things with SQL is always fun...

This Sudoku solver makes use of Oracle 10g's MODEL clause, which seems quite hairy.

SQL isn't mentioned around here all that often, so I am glad we can at least remind ourselves from time to time of the most heavily used declarative language out there by posting SQL puzzles and hacks...

AngloHaskell 2007

Following on from last year, I've started organising an AngloHaskell event for 2007. It's early days yet, but planning is taking place on the haskell wiki at http://www.haskell.org/haskellwiki/AngloHaskell and on #anglohaskell on irc.freenode.net - anyone who might attend is welcome to join in the discussion.

Last year's event was good fun, featuring practically-oriented and hobbyist talks, punting and plenty of pub time. The organisation process may seem a little haphazard, but an important part of laziness is being able to evaluate things when they are in fact demanded! On that basis, a time and a venue are the first order of business.

LC for kids (alligators, oh my!)

(via Wadler)

A visual LC game.

You can show it to the kids, or try to guess what each element in the game represents before reading the explanation at the end...

Yesno

Yesno: the other side ot the Gödelian coin

Any universally powerful programming language must either offer consistent semantics, or allow the possibility of programs not halting. … Almost all programming languages to date choose consistency. … Yesno is an inconsistent and complete programming language, and that every program returns a value.

Interactivity considered harmful

After reading many posts lauding interactive tools as an integral part of the next big thing in software development, I figured I could offer this as counterpoint. The paper Magic Ink: Information Software and the Graphical Interface very eloquently argues that most software today, especially information-intensive software (think IDEs and many other GUI-based PL tools) are really badly designed. The most memorable section subtitle being interactivity considered harmlful. This is a real treasure trove of wonderful design ideas for interfaces for information-rich applications.

This paper follows in the grand tradition of Edward Tufte, whose book The Visual Display of Quantitative Information was an incredible revelation for me.

Somehow, I do think that some of the ideas behind Intentional Software fit in here -- although I make no claim as to whether the actual implementation of those ideas is an appropriate realization.

Ninety-nine Lisp Problems

As Lemonodor says: 99 Problems But malloc Ain't One of Them.

Anyway, the list is based on on a list of Prolog challenges, but the solutions (when they exist) are in Lisp.

Self-Reproducing Programs in Common Lisp

Self-Reproducing Programs in Common Lisp by Peter Norvig, 1990.

This paper reviews the classic self-reproducing expressions in Lisp, and presents some new ones that are unique to Common Lisp.

Writing A Lisp Interpreter In Haskell

(via Windley)

This seems like a nice writeup. The article even manages to introduce monads (without explicitly going into all the details), and provides the correct perspective about them (i.e., they are not just for IO). Also featured: Parsec and a bit irony (see footnote #2).

Holodeck games and CCCs

From the n-Category Cafe, some notes on Holodeck Games and cartesian closed categories.

This also appeared here (and was mentioned by Phil Wadler). The two posts seem to have different addenda, comments and links, so it may be worth looking at both.

It's fun to see lambda calculus introduced to an audience already familiar with categories, as that seems to be the opposite of the usual state of affairs around here, and I can think of certain LtU regulars who will hopefully find this whole subject enjoyable.

A Madman Dreams of Turing Machines

Here's something a little unusual... a novel.

A Madman Dreams of Turing Machines. Janna Levin.

In this remarkable work of fiction, astrophysicist Janna Levin reimagines the lives of two of the most important and influential minds of our time.

The narrator is a scientist herself, a physicist obsessed with Kurt Gödel, the greatest logician of many centuries, and with Alan Turing, the extraordinary mathematician, breaker of the Enigma Code during World War II.

The potential interest to this audience should be fairly obvious, although the book is centered at least as much on their substantial personal struggles as on their work. Here is the New York Times review, perhaps it would be nice to have an LtU review as well...

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