=================================================================
Logtalk - Object oriented extension to Prolog
Release 2.21.1

Copyright (c) 1998-2004 Paulo Moura.  All Rights Reserved.
=================================================================


% start by loading the example:

| ?- logtalk_load(loader).
...


% create four bricks, all standing on the "ground" (use your imagination... ;-)

| ?- brick::new(a, [position-(8, 1)]).
yes

| ?- brick::new(b, [position-(6, 1)]).
yes

| ?- brick::new(c, [position-(4, 1)]).
yes

| ?- brick::new(d, [position-(2, 1)]).
yes

% set up ascii stack monitor so we can watch the bricks moving

| ?- after_event_registry::set_monitor(_, move(_,_), _, stack_monitor).
yes


% make the stack

| ?- brick_stack::add_tuple([c,d]).
|.c......
|.d...b.a
---------
yes

| ?- brick_stack::add_tuple([b,c]).
|.b......
|.c......
|.d.....a
---------
yes

| ?- brick_stack::add_tuple([a,b]).
|.a
|.b
|.c
|.d
---
yes


% check results

| ?- brick_stack::tuple(Tuple), write(Tuple), nl, fail.
[c,d]
[b,c]
[a,b]
no

| ?- before_event_registry::monitors(Mb), after_event_registry::monitors(Ma).
Ma = [brick_stack, stack_monitor] 
Mb = [brick_stack]
yes


% move all stack to new position by moving bottom brick; check results

| ?- d::move(9, 1).
|.a.......
|.b.......
|.c.......
|........d
----------
|.a.......
|.b.......
|........c
|........d
----------
|.a.......
|........b
|........c
|........d
----------
|........a
|........b
|........c
|........d
----------
yes

| ?- a::position(Xa, Ya), b::position(Xb, Yb), c::position(Xc, Yc), d::position(Xd, Yd).
Xa = 9,
Xb = 9,
Xc = 9,
Xd = 9,
Ya = 4,
Yb = 3,
Yc = 2,
Yd = 1
yes

| ?- brick_stack::tuple(Tuple), write(Tuple), nl, fail.
[c,d]
[b,c]
[a,b]
no


% break stack in half by moving b to the "ground"; check results

| ?- b::move(3, 1).
|........a
|.........
|........c
|..b.....d
----------
|..a.....c
|..b.....d
----------
yes

| ?- a::position(Xa, Ya), b::position(Xb, Yb), c::position(Xc, Yc), d::position(Xd, Yd).
Xa = 3,
Xb = 3,
Xc = 9,
Xd = 9,
Ya = 2,
Yb = 1,
Yc = 2,
Yd = 1
yes

| ?- brick_stack::tuple(Tuple), write(Tuple), nl, fail.
[c,d]
[a,b]
no


% create new brick_stack tuple ; check results

| ?- brick_stack::add_tuple([d, a]).
|..d......
|..a.....c
|..b......
----------
|..c
|..d
|..a
|..b
----
yes

| ?- a::position(Xa, Ya), b::position(Xb, Yb), c::position(Xc, Yc), d::position(Xd, Yd).
Xa = 3,
Xb = 3,
Xc = 3,
Xd = 3,
Ya = 2,
Yb = 1,
Yc = 4,
Yd = 3
yes

| ?- brick_stack::tuple(Tuple), write(Tuple), nl, fail.
[c,d]
[a,b]
[d,a]
no


% move all stack to new position by moving bottom brick; check results

| ?- b::move(5, 1).
|..c..
|..d..
|..a..
|....b
------
|..c..
|..d..
|....a
|....b
------
|..c..
|....d
|....a
|....b
------
|....c
|....d
|....a
|....b
------
yes

| ?- a::position(Xa, Ya), b::position(Xb, Yb), c::position(Xc, Yc), d::position(Xd, Yd).
Xa = 5,
Xb = 5,
Xc = 5,
Xd = 5,
Ya = 2,
Yb = 1,
Yc = 4,
Yd = 3
yes

| ?- brick_stack::tuple(Tuple), write(Tuple), nl, fail.
[c,d]
[a,b]
[d,a]
no


% clean up instances, tuples and monitors

| ?- brick_stack::remove_all_tuples.
yes

| ?- after_event_registry::del_monitors(_, _, _, stack_monitor).
yes

| ?- brick::delete_all.
yes