Files
mercury/tests/trailing/func_trail_test_2.m
2023-09-18 21:54:30 +10:00

120 lines
2.7 KiB
Mathematica

%---------------------------------------------------------------------------%
% vim: ts=4 sw=4 et ft=mercury
%---------------------------------------------------------------------------%
:- module func_trail_test_2.
:- interface.
:- import_module io.
:- pred main(io::di, io::uo) is det.
:- implementation.
:- import_module int.
:- pragma promise_pure(main/2).
main(!IO) :-
( impure trail_test ->
io.write_string("Success\n", !IO)
;
io.write_string("Failure\n", !IO)
).
:- impure pred trail_test is failure.
trail_test :-
small_int(I),
impure trail_test_message("before", I, 0),
impure enter(I),
small_int_2(J),
small_int(J),
impure trail_test_message("inside", I, J),
impure leave(I),
impure trail_test_message("after", I, J),
fail.
:- pred small_int(int::out) is multi.
small_int(1).
small_int(2).
small_int(3).
:- pred small_int_2(int::out) is multi.
small_int_2(4).
small_int_2(5).
small_int_2(6).
:- impure pred trail_test_message(string::in, int::in, int::in) is det.
:- impure pred enter(int::in) is det.
:- impure pred leave(int::in) is det.
:- pragma foreign_decl("C", "
#include <stdio.h>
#include \"mercury_trail.h\"
void trace_redo(int handle, MR_untrail_reason reason);
void trace_fail(int handle, MR_untrail_reason reason);
").
:- pragma foreign_proc("C",
trail_test_message(Prefix::in, I::in, J::in),
[will_not_call_mercury, will_not_modify_trail],
"
printf(""%s: %d %d\\n"", (char *)Prefix, (int)I, (int)J);
").
:- pragma foreign_code("C", "
void trace_fail(int handle, MR_untrail_reason reason) {
switch (reason) {
case MR_exception:
case MR_undo:
case MR_retry:
/* printf(""trace_fail: exception/undo/retry\\n""); */
printf(\"<= fail: %d\\n\", handle);
break;
default:
printf(\"trace_fail: default\\n\");
break;
}
}
void trace_redo(int handle, MR_untrail_reason reason) {
switch (reason) {
case MR_exception:
case MR_undo:
case MR_retry:
/* printf(""trace_redo: exception/undo/retry\\n""); */
printf(\">= redo: %d\\n\", handle);
break;
case MR_commit:
case MR_solve:
printf(\"trace_redo: commit/solve\\n\");
break;
default:
printf(\"trace_redo: default\\n\");
/* we may need to do something if reason == MR_gc */
break;
}
}
").
:- pragma foreign_proc("C",
enter(I::in),
[will_not_call_mercury],
"
printf(\">> enter (%d)\\n\", (int) I);
MR_trail_function(trace_fail, (void *) I);
").
:- pragma foreign_proc("C",
leave(I::in),
[will_not_call_mercury],
"
printf(\"<< leave (%d)\\n\", (int) I);
MR_trail_function(trace_redo, (void *) I);
").