Warren Harris
However, the use of a universal type for the values would still seem to be required since there is no way to implement type-indexed values when the queries themselves are expressed as an abstract datatype rather than as functions. Am I overlooking something?
You might find inspiration in the fact that printf and scanf can be expressed in ML/Haskell without any fancy type-system features. http://www.brics.dk/RS/98/12/ http://cs.nyu.edu/zheyang/papers/YangZ--ICFP98.html http://article.gmane.org/gmane.comp.lang.haskell.general/16409 http://www.itu.dk/people/mir/typesafepatterns.pdf Credits to: Olivier Danvy, Zhe Yang, Kenichi Asai, Oleg Kiselyov, Morten Rhiger. -- Edit this signature at http://www.digitas.harvard.edu/cgi-bin/ken/sig 2008-11-20 Universal Children's Day http://unicef.org/ 1948-12-10 Universal Declaration of Human Rights http://everyhumanhasrights.org