> than version you've wrote in CL. i would write it like this:
>
> (defun factorial (n)
> (loop with p = 1
> for i from 1 to n
> do (setf p (* p i))
> finally (return p)))
>
> IMHO that's cleaner. or if i absolutely must use recursion:

Gauche Scheme (using lazy iota):

(define (fac n) (fold * 1 (liota n 1)))

(fac 6)
===>
720

(fac 5)
===>
120

In Forth?

lauantai 19. maaliskuuta 2022 klo 12.18.06 UTC+2 Robert L. kirjoitti:
> > than version you've wrote in CL. i would write it like this:
> >
> > (defun factorial (n)
> > (loop with p = 1
> > for i from 1 to n
> > do (setf p (* p i))
> > finally (return p)))
> >
> > IMHO that's cleaner. or if i absolutely must use recursion:
>
> Gauche Scheme (using lazy iota):
>
> (define (fac n) (fold * 1 (liota n 1)))
>
> (fac 6)
> ===>
> 720
>
> (fac 5)
> ===>
> 120
>
> In Forth?

8th includes factorial inside the library:

needs math/factorial

6 n:! . cr
5 n:! . cr

I have a challenge for you:

\
\ Fibonacci with million digits for the 8th programming language
\ : bits? \ n -- nbits-1
n:ln 2 n:ln n:/ n:int ;

: fiboloop
>r 2dup 2 n:*
over n:-
n:* -rot
n:sqr swap n:sqr n:+
r> r@ swap n:shr 1 n:band if
dup rot n:+
then ;

: fibo \ n -- fibo(n)
>r F0 F1
' fiboloop 1 r@ bits? loop-
r> 1 n:band if
n:sqr swap n:sqr n:+
else
2 n:* over n:- n:*
then ;

: app:main
1000000 n#
4784969 fibo
"%.f" strfmt \ Convert result to just an 'int' string.
s:len . " digits:" . cr
dup 40 s:lsub . " upper 40 digits" . cr
40 s:rsub . " lower 40 digits" . cr ;

In Scheme?

On Saturday, March 19, 2022 at 2:58:33 PM UTC+1, Jali Heinonen wrote:
Fastest factorial in the world (32bit and 64bit) :

create (factorial)
1 , 1 , 2 , 6 , 24 , 120 , 720 , 5040 , 40320 , 362880 , 3628800 ,
39916800 , 479001600 ,

/cell 4 - [IF] \ 64bit version
20 constant max-factorial

6227020800 , 87178291200 , 1307674368000 , 20922789888000 , 355687428096000 ,
6402373705728000 , 121645100408832000 , 2432902008176640000 ,
[ELSE]

12 constant max-factorial \ 32bit version
[THEN]

: factorial max-factorial min cells (factorial) + @c ;

... and still only 25 opcodes (4tH 64bits)!

Hans Bezemer