Files
mercury/tests/tabling/tc_memo2.m
2018-07-08 23:20:52 +02:00

46 lines
776 B
Mathematica

%---------------------------------------------------------------------------%
% vim: ts=4 sw=4 et ft=mercury
%---------------------------------------------------------------------------%
:- module tc_memo2.
:- interface.
:- import_module io.
:- pred main(io::di, io::uo) is det.
:- implementation.
:- import_module list.
:- import_module std_util.
:- pragma require_feature_set([memo]).
main(!IO) :-
( if
tc(1, 4),
tc(3, 4)
then
io.write_string("yes\n", !IO)
else
io.write_string("no\n", !IO)
).
:- pred tc(int::in, int::out) is nondet.
:- pragma memo(tc/2).
tc(A, B) :-
edge(A, C),
(
B = C
;
tc(C, B)
).
:- pred edge(int::in, int::out) is nondet.
edge(1, 2).
edge(1, 3).
edge(3, 4).