Re: the necessity of Lisp's Objects?

George Neuner  <gneuner2/@[EMAIL PROTECTED]
> wrote:
+---------------
| rpw3@[EMAIL PROTECTED]
 (Rob Warnock) wrote:
| >Well, true, but you can keep the internal name from escaping by
| >returning the function value, making it effectively "anonymous":
| >
| >    > (funcall
| >       (labels ((self (x) (if (< x 2) 1 (* x (self (1- x)))))) #'self)
| >       5)
| >
| >    120
| >    > 
| 
| Yes, I suppose that is anonymous in the way John intended.
| 
| It's a little more verbose in Scheme:
| 
|  ((lambda (x)
|    (let self ((x x)) 
|      (if (< x 2) 1 (* x (self (- x 1))))))
|   5)
|  120
| 
| but I think the Scheme makes it a little clearer that there is a named
| self referential function in an anonymous wrapper.  
+---------------

That's using the "named LET", though you also can do it in Scheme
almost exactly the same way I did in CL, by using LETREC instead
of LABELS and leaving off the FUNCALL:

    > ((letrec ((self (lambda (x) (if (< x 2) 1 (* x (self (1- x)))))))
	 self)
       5)
    120
    > 


-Rob

-----
Rob Warnock			<rpw3@[EMAIL PROTECTED]
>
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