I have a problem with the code of conduct of
the group New PIP proposals - Prolog Community
which is not free speech friendly. It says:

If You See a Problem, Flag It
https://discourse.prolog-lang.org/faq

Thats not a good approach since it can be
easily abused. What I think is a better approach
are individual kill files, like in the good old

USENET times. Interestingly plonk is also provided
by discourse. For example in SWI-Prolog discourse
I can go to a user, and choose ignore indefinitely:

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Ok, I tried a native implementation of variant/2.
I did it in Dogelog Player for Java. Thats a
Prolog system that doesn't have unification for

cyclic terms. So the situation is a little simpler.
Comparing on the same machine and with the data
we have already gathered it is shockingly fast!

/* Dogelog Player 1.2.4, JDK 22 */

?- time(test).
% Zeit 211 ms, GC 0 ms, Lips 7567459, Uhr 15.10.2024 01:30
true.

?- time(test2).
% Zeit 413 ms, GC 0 ms, Lips 10703217, Uhr 15.10.2024 01:30
true.

Here some results:

- SWI-Prolog 9.3.11:

?- time(test).
% 2,126,498 inferences, 0.734 CPU in 0.752 seconds
(98% CPU, 2895657 Lips)
true.

?- time(test2).
% 2,159,795 inferences, 0.234 CPU in 0.236 seconds
(99% CPU, 9215125 Lips)
true.

- Trealla Prolog 2.57.16:

?- time(test).
% Time elapsed 3.128s, 14827949 Inferences, 4.741 MLips
true.

?- time(test2).
% Time elapsed 1.079s, 7775516 Inferences, 7.206 MLips
true.

- Scryer Prolog :

?- time(test3).
% CPU time: 5.653s, 5_192_831 inferences
true.

?- time(test2).
% CPU time: 1.544s, 6_116_163 inferences
true.

Note: test3 is like test, only it uses builtins:variant/2.

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