search

ljos / ob-prolog

Org babel functions for prolog evaluation.
12 stars 6 forks source link

Querying without adding to database? #24

Open borgauf opened 1 year ago

borgauf commented 1 year ago

Could you enlighten us on exactly how the goal querying works? For example, I've got a query that has multiple answers, but I seem to only get the first one.

`child(john,sue). child(john,sam). child(jane,sue). child(jane,sam). child(sue,george). child(sue,gina).

male(john).

male(sam). male(george). female(june). female(sue). female(jane).

parent(Y,X) :- child(X,Y).

father(Y,X) :- child(X,Y), male(Y).

opp_sex(X,Y) :- male(X), female(Y). opp_sex(Y,X) :- male(X), female(Y).

grand_father(X,Z) :- father(X,Y), parent(Y,Z).`

`#+NAME: grandfather1

+HEADER: :session prolog-sess

+HEADER: :goal gf(X,Z)

+BEGIN_SRC prolog

gf(X,Z) :- grand_father(X,Z).

+END_SRC

+RESULTS: grandfather1

| A | = | george, | | B | = | john. |`

There should be a george, jane match too. So how do you get the SWI ";" behavior?

ljos commented 1 year ago

With a session it purposefully cuts the evaluation. See L215. It shouldn't be impossible to change the code to support being able to list out all results, but the easiest for you now is to instead find all the goals of a solution.

borgauf commented 1 year ago

Yes, thank you. I've got this working

+begin_src prolog :results output :session prolog-sess

child(john,sue). child(john,sam). child(jane,sue). child(jane,sam). child(sue,george). child(sue,gina). child(pete,hank). child(hank,roy).

+end_src

+name: allchildren1

+HEADER: :session prolog-sess

+HEADER: :goal list_children1(P,L)

+begin_src prolog :exports both :results verbatim

list_children(P,L) :- findall(Child, child(Child, P), L).

+end_src

+RESULTS: allchildren1

: Correct to: "list_children(P,L)"? L = [john, john, jane, jane, sue, sue, pete, hank].

Now, could you help me get this into elisp? I'm trying

+begin_src emacs-lisp :var chlist=allchildren1()

chlist

+end_src

but it gives no output. Obviously, I'm trying to get the L list. Once I have this figured out I'll be good to go for a long while with Prolog and ob-prolog.

On Thu, Feb 16, 2023 at 3:18 AM Bjarte Johansen @.***> wrote:

With a session it purposefully cuts the evaluation. See L215 https://github.com/ljos/ob-prolog/blob/331899cfe345c934026c70b78352d320f7d8e239/ob-prolog.el#L216. It shouldn't be impossible to change the code to support being able to list out all results, but the easiest for you now is to instead to find all the goals of a solution https://www.swi-prolog.org/pldoc/man?section=allsolutions.

— Reply to this email directly, view it on GitHub https://github.com/ljos/ob-prolog/issues/24#issuecomment-1432766127, or unsubscribe https://github.com/notifications/unsubscribe-auth/ABA73W6PSTD4AR5SZ3H3EEDWXXWG3ANCNFSM6AAAAAAUYBUTJU . You are receiving this because you authored the thread.Message ID: @.***>

-- ⨽ Lawrence Bottorff Grand Marais, MN, USA @.***