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

63 lines
1.4 KiB
Mathematica

%---------------------------------------------------------------------------%
% vim: ts=4 sw=4 et ft=mercury
%---------------------------------------------------------------------------%
%
% This test is a variant of coup, with the commits around the recursive
% calls wrapped up inside explicit predicates. This means that when a
% subgoal is suspended, coup_det_frame will require a non-empty det
% stack segment to be saved, whereas in coup the saved det stack segment
% is empty. Both need to be tested.
%
% In case there are any problems with the interaction of the commits
% and tabling, this version is more likely to be easy to debug, since
% putting breakpoints on any_p and any_q effectively puts breakpoint
% on the commits, which otherwise you can't easily do.
:- module coup_det_frame.
:- 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).
:- pragma minimal_model(p/1).
:- pred p(int).
:- mode p(out) is nondet.
p(X) :-
q(X).
p(X) :-
X = 1.
:- pragma minimal_model(q/1).
:- pred q(int).
:- mode q(out) is nondet.
q(3) :-
any_q.
q(4) :-
any_p.
:- pred any_q is semidet.
any_q :-
q(_).
:- pred any_p is semidet.
any_p :-
p(_).