Lambda the Ultimate

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Came across this in my referrers log and thought it might be of interest to others. Reminds in scope of GEB, meandering through Number Theory, Category Theory, Combinatorial Logic, Metaphysics, AI and the Semantic Web, touching programming language issues along the way. Lots of loose ends and uneven in flow but there's various gems scattered throughout (I thought the section that explains CT was good).

What have we learnt on our trip around the fascinating perspectives and problems of a Dynamic Semantic Web? It is all about dynamics and structures. This brings us back to the central topics of DERRIDA'S MACHINES: Interactivity between structures and dynamics, that is, to the interplay of algebras and co-algebras, ruled by category theory and surpassed by the diamond strategies leading to polycontexturality and kenogrammatics.

Guess I'll have to work on my vocabulary as I've never heard of polycontexturality and kenograms.

This is the final version of a paper accepted for Embedded Software Conference 2004. The paper doesn't show any circuits but the straight-line C code should be implementable easily.

There is a significant difference from FFTW in that the authors don't do any intensional code analysis -- the generated code is black box and can't be processed nor manipulated any further. Moreover, the generated code can't even be compared by equality. Oleg tells me that the paper is somewhat obsolete: it says that they approach FFTW in the number of operations in the generated code. That is no longer true: the power-two FFT generated code has exactly the same number of floating-point operations as that in codelets of FFTW.

Abstract interpretation is used to fix several problems in the generated code. This makes some optimizations possible (e.g., avoiding code duplication).

Multi-stage programming fans, enjoy!

Icon has always impressed me as the most elegant and useful string processing language. In fact, I still use it. The speed impresses me to this day. Lately the out-of-print Implementation of the Icon Programming Language book went online as a PDF download. Not only that, the copyright is public domain.

The successor language Unicon has published the first issue of The Generator, a journal devoted to that language. Unicon is an open-source project. Therefore code from the Icon implementation book lives in Unicon's public code repository. What Unicon adds to Icon is OO, POSIX, and other goodies.

My own plea is for language folks to study (Un-)Icon's string scanning mechanisms. How I wish they were more common. No matter what my task or language du jour, I always find myself longing for Icon when it comes to strings. Doug Bagley offers some OCaml libraries which imitate Icon string techniques.