AW: [Haskell-cafe] Fixed-Point Combinators

--- Adrian Neumann schrieb am Mi, 16.7.2008:

Von: Adrian Neumann Betreff: [Haskell-cafe] Fixed-Point Combinators An: "Haskell Cafe mailing list" Datum: Mittwoch, 16. Juli 2008, 21:17 Hello,

while studying for a exam I came across this little pearl:

Y = (L L L L L L L L L L L L L L L L L L L L L L L L L L L L) where L = λabcdefghijklmnopqstuvwxyzr. (r (t h i s i s a f i x e d p o i n t c o m b i n a t o r))

posted by Cale Gibbard to this list. Now I'm wondering how exactly does one finde such awesome λ expressions? Is there some mathemagical background that lets one conjure such beasts?

Have a look at http://citeseer.ist.psu.edu/251224.html In this paper Jeroen Fokker describes how to derive a one-combinator basis from the SKI combinators in a systematic way. Maybe it can give you some hints how to treat this kind of problem. __________________________________________________________ Gesendet von Yahoo! Mail. Dem pfiffigeren Posteingang. http://de.overview.mail.yahoo.com