The Teyjus system is an efficient implementation of the higher-order logic programming language Lambda Prolog. The main strength of Lambda Prolog, a language developed by Dale Miller and Gopalan Nadathur, is the support it offers for what is known as lambda tree syntax, a new and effective way to view the structure of complex syntactic objects such as types, formulas, proofs and programs. Lambda Prolog provides this support by using lambda terms as data representation devices and by including primitives for probing such terms in logically meaningful ways. The new features present in the language raise several implementation challenges that have been addressed in collaborative work between Nadathur and his students and colleagues. The name "Teyjus" actually stands both for a project and for a class of compiler and virtual machine based realizations of Lambda Prolog arising from the research carried out within this project. Underlying the most recent version of the Teyjus system is a new and significantly improved virtual machine that has been designed by Xiaochu Qi as part of her doctoral dissertation work at the University of Minnesota. This virtual machine extensively exploits a special form of higher-order unification known as pattern unification.

I found this article saying that Atari has released the source code for some 7800 games like Ms. Pac Man, Dig Dug, Centipede, and Joust. So if your bored this weekend you might find some enjoyment going threw the source code of your favorite Atari game.

DirectJNgine is feature complete, providing support for all kinds of requests: batched json requests, form posts with file uploads, requests from polling providers, etc. A detailed User's Guide (more than 20 pages) is part of distribution: you can read it in 'http://directjngine.googlecode.com/files/DirectJNgine%20User%27s%20Guide.0.7.1.beta.pdf'.

This release is dedicated to my grandfather, Walter Gordon Heffron, who introduced me to Unix 30 years ago, and who passed away yesterday.

The July edition of GroovyMag is out! There's a lot of great articles in it including the one I authored entitled 'Inline Editing with jQuery'. The goal of the article is to teach the user how to create an inline editable datatable which supports editing with textfields, textareas, select lists, and datepickers. On top of all that is sprinkled a healthy dose of ajaxy goodness.

An update has been released for initial preview release of MySQL 5.4. The release contains scalability improvements and additional DTrace probes for diagnostic troubleshooting on Solaris.