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Unexpected result with findall/3

See original GitHub issue

For the following program in http://tau-prolog.org/sandbox/

test :-
    findall([A,_],p(A,_),L),
    write(L),
    nl.

p(a,b).
p(c,d).
p(e,f).

the query

test.

gives

[[a,__2],[c,__2],[e,__2]]

whereas the expectation is somtehing like

[[a,_2],[c,_3],[e,_4]]

Issue Analytics

State:
Created 2 years ago
Reactions:1
Comments:11 (4 by maintainers)

Top GitHub Comments

2reactions

pmouracommented, Feb 7, 2022

That clarifies it, thanks. Test added (https://github.com/LogtalkDotOrg/logtalk3/commit/72f5836dc190ccae4a4280c5085ac8981132aa3f).

2reactions

jariazavalverdecommented, Feb 7, 2022

@pmoura Try with a variable not in the goal. You should get something like:

?- assertz(f(1)).
true.

?- assertz(f(2)).  
true.

?- findall((B,A), f(A), [(B1,1),(B2,2)]), B1 \== B2.
false.

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