Re: primitive recursive

Barb Knox <see@xxxxxxxxx> writes:

> In article <n3XDe.191671$75.8294931@xxxxxxxxxxxx>,
> "n3wb1e" <n3wb1e@xxxxxxxxxxxxxx> wrote:
>
>>can someone show me an example of recursive function who is not primitive
>>recursive (other than Ackermann's function)?
>>Thank you.
>
> If you know Lisp, consider the eval function.

Why is the function `eval' not primitive recursive? (What's the
definition of the set of primitive recursive Lisp functions, anyway?)

> If you know Lambda Calculus or combinatory logic, consider any of the
> fixed-point operators.

Why isn't \f.(\x.f(xx))(\x.f(xx)) primitive recursive?

Jesse

--
Jesse Alama (alama@xxxxxxxxxxxx)
.