On 31 mars 06, at 23:01, Thomas Fischbacher wrote:

>
>> I guess that this is not a lambda term that can be typed.
>> There are many of them. A famous one is the Y combinator.
>> The _typed_ lambda calculus does not allow all the lambda terms
>> of the (normal) lambda calculus.
>
> # let rec y f = f (y f);;
> val y : ('a -> 'a) -> 'a = <fun>

I know that, but you cheat. This not a lambda calcul Y combinator.


>
> --  
> regards,               tf@cip.physik.uni-muenchen.de              (o_
>  Thomas Fischbacher -  http://www.cip.physik.uni-muenchen.de/~tf  //\
> (lambda (n) ((lambda (p q r) (p p q r)) (lambda (g x y)           V_/_
> (if (= x 0) y (g g (- x 1) (* x y)))) n 1))                   
> (Debian GNU)
>