maplist/2: Unexpected nondeterminism with clpz

[triska]

With the following program:

:- use_module(library(clpz)).

all_eq(Vs, E) :- maplist(#=(E), Vs).

We have:

?- maplist(all_eq([A]), [0]).
   A = 0
;  A = 0, unexpected.

Expected: A = 0, deterministic success.

[UWN]

(This is rather an issue of an unexpected, redundant answer. Excellent occasion to note that redundant should come before unexpected).

?- maplist(all_eq([A]), [0]).
   A = 0
;  A = 0, redundant, unexpected.
   A = 0.

Also note that unexpected only ensures that this second answer is unexpected. It does not state what is expected. Instead, also say A = 1 could be a valid answer. Because of this it is necessary to restate again what actually is expected.

[triska]

Thank you a lot!

[triska]

This issue is now unfortunately again present, so I am reopening it.

[triska]

Thank you a lot, again!