Starting with the Sudoku solver we have recently
obtained we developed a Puzzle generator together
with an interactive game play. The result can be
run in a web page by means of Dogelog Player 1.2.0
for JavaScript. Both the Puzzle generator and the
game play were written in 100% Prolog.

Regin Filtering from SWI-Prolog CLP(FD) didn’t
make a dent for generating unique puzzles, all we
could do was provide 34 clues, and our solver takes
in the average 1000 ms. We also implemented valid
move checking by reusing the constraints and an undo
move queue via dynamic facts.

See also:

Game Play of Spock Doku
https://twitter.com/dogelogch/status/1774936304335159561

Game Play of Spock Doku
https://www.facebook.com/groups/dogelog

Mild Shock schrieb:
>
> Dogelog Player is a Prolog system that features
> a generational garbage collector scheme and a
> change_arg/3 primitive built-in. So far the two
> didn’t go together and we had to use a cludge.
> With the upcoming release we provide a proper
> solution based on marking write-barriers.
>
> Our remembered set on the variable binding trail
> has the benefit that it can reduce itself during
> backtracking. By adopting conductor variables, i.e.
> instantiated variables that are not trailed, from
> formerly Jekejeke Prolog, we could recreate a
> similar benefit for Dogelog Players change_arg/3.
>
> See also:
>
> Marking Write-Barriers for Dogelog Player
> https://twitter.com/dogelogch/status/1771559896741192186
>
> Marking Write-Barriers for Dogelog Player
> https://www.facebook.com/groups/dogelog