Files
mercury/tests/tabling/generator_in_commit.m
2018-07-08 23:20:52 +02:00

54 lines
1.0 KiB
Mathematica

%---------------------------------------------------------------------------%
% vim: ts=4 sw=4 et ft=mercury
%---------------------------------------------------------------------------%
%
% This test case checks whether we get incorrect answers
% when a generator gets started but not finished inside a commit.
% One possible problem it tests for is not cleaning up the consumers
% of such generators properly.
:- module generator_in_commit.
:- interface.
:- import_module io.
:- pred main(io::di, io::uo) is det.
:- implementation.
:- import_module int.
:- import_module list.
:- import_module solutions.
:- pragma require_feature_set([memo]).
main(!IO) :-
solutions(p, Solns),
io.write(Solns, !IO),
io.write_string("\n", !IO).
:- pred p(int).
:- mode p(out) is nondet.
p(X) :-
(
q(_),
X = 42
;
q(Y),
X = Y + 20
).
:- pragma minimal_model(q/1).
:- pred q(int).
:- mode q(out) is nondet.
q(X) :-
(
q(Y),
X = Y + 1,
X < 4
;
X = 1
).