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@TZUTC: -0700
@PID: G2/1.0
@TID: FIDOGATE-5.12-ge4e8b94
Whats the Scryer Performance of this Example?

/* GNU Prolog 1.5.0 */
?- between(1,200,N), length(L,N), nth_member(I,L,E), fail; true.
(94 ms) yes

/* SWI-Prolog 9.1.14 */
?- time((between(1,200,N), length(L,N), nth_member(I,L,E), fail; true)).
% 94,504,524 inferences, 4.766 CPU in 4.767 seconds (100% CPU, 19830457 Lips)
true.

That was measured on my machine,
and was a factor ca. 50x slower in SWI-Prolog.

Source Code:

nth_member(1, [M|_], M).
nth_member(N, [_|T], M) :-
  N #> 1, N1 #= N - 1,
  nth_member(N1, T, M).
--- G2/1.0
 * Origin: usenet.network (2:5075/128)
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