Readers of this list may enjoy the following note by Martin Escardo, which shows how to write a number of "seemingly impossible Haskell programs" that perform exhaustive searches over spaces of infinite size, by exploiting some ideas from topology: http://math.andrej.com/2007/09/28/seemingly-impossible-functional-programs/#... Have fun! Graham +-----------------------------------------------------------------+ | Dr Graham Hutton Email : gmh@cs.nott.ac.uk | | School of Computer Science | | University of Nottingham Web : www.cs.nott.ac.uk/~gmh | | Jubilee Campus, Wollaton Road | | Nottingham NG8 1BB, UK Phone : +44 (0)115 951 4220 | +-----------------------------------------------------------------+ This message has been checked for viruses but the contents of an attachment may still contain software viruses, which could damage your computer system: you are advised to perform your own checks. Email communications with the University of Nottingham may be monitored as permitted by UK legislation.