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From: Julio Di Egidio <julio@diegidio.name>
Newsgroups: comp.lang.prolog
Subject: Can we do this with ancestral cuts or something?
Date: Mon, 9 Dec 2024 14:35:20 +0100
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Given a list of goals representing a conjunction, I would like it to 
fail as soon as any goal fails, but I would like *not* to cut on the 
search space otherwise.

Here is my actual test case, only considering ground goals (otherwise 
too many ways to play with it that seem immaterial to the problem):

```
red(1).
red(1).

and([]) :- !.  % with Xs ground!
and([H:B|Xs]) :-
	red(B), writeln(H:B),
	and(Xs).

/*

Actual:
-------

?- and([x:1,y:1]), fail.  % ok: full search space
x:1
y:1
y:1
x:1
y:1
y:1
false.

?- and([x:1,y:0]), fail.  % KO: could fail earlier
x:1
x:1
false.

Expected:
---------

?- and([x:1,y:0]), fail.  % ok: fails early!
x:1
false.

*/
```

Am I just missing something obvious?  I am trying with "ancestral cuts" 
(SWI-Prolog has these), but I have not yet found a solution.

-Julio