Lambda the Ultimate

Ziggurat is a framework for writing extensible programming languages, and for defining static semantics for those languages. In other words, it is a language designer's toolkit.

Ziggurat is based on macros. When building a language using Ziggurat, it is easy to make that language extensible by adding a macro system. Ziggurat macros allow for incremental extension of the language by rewriting. What makes Ziggurat different from other macro systems is that Ziggurat allows the language extender to optionally define static semantics for her new language, and connect these static semantics amongst language levels. This makes it possible to write specialized analysis algorithms for the higher-level languages, either for optimization purposes, profiling purposes, debugging purposes, or whatever task analysis is put to.

Strangely enough this project from Olin Shivers and David Fisher was not mentioned here before.

Those with access may want to check out the paper on Ziggurat in the September 2008 double issue of JFP.

McCarthy's Elephant language proposal was mentioned here several times in the past. This talk from Etech provides a nice introduction to the fundamental idea behind Elephant and its background.

The talk includes interesting, though not entirely motivated, comments related to the paper Ascribing Mental Qualities to Machines. This is one of McCarthy's most significant papers in my opinion, and deserves more attention and debate. It is also rather amusing. I hope I will find the time some day to put this paper in context (McCarthy's comments in the Etech talk notwithstanding), but for the time being I recommend it to anyone interested in this sort of thing.

One thing is for sure: We can safely add to the 2009 predictions the prediction that Elephant will not be ready in 2009...