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:- object(brick,
instantiates(class),
specializes(object)).
:- info([
version is 1.1,
date is 2000/10/31,
author is 'Paulo Moura',
comment is 'Two-dimensional brick (or should I say square?) class.']).
:- public(position/2).
:- mode(position(?integer, ?integer), zero_or_one).
:- info(position/2, [
comment is 'Brick current position.',
argnames is ['X', 'Y']]).
:- private(position_/2).
:- dynamic(position_/2).
:- mode(position_(?integer, ?integer), zero_or_one).
:- info(position_/2, [
comment is 'Stores brick current position.',
argnames is ['X', 'Y']]).
:- public(move/2).
:- mode(move(+integer, +integer), one).
:- info(move/2, [
comment is 'Moves a brick to a new position.',
argnames is ['X', 'Y']]).
position(X, Y) :-
::position_(X, Y).
move(X, Y) :-
::retractall(position_(_, _)),
::assertz(position_(X, Y)).
default_init_option(position-(0, 0)).
default_init_option(Default) :-
^^default_init_option(Default).
process_init_option(position-(X, Y)) :-
::assertz(position_(X, Y)).
process_init_option(Option) :-
^^process_init_option(Option).
valid_init_option(position-(X, Y)) :-
!,
integer(X),
integer(Y).
valid_init_option(Option) :-
^^valid_init_option(Option).
instance_base_name(b).
:- end_object.
:- object(brick_stack,
instantiates(constrained_relation)).
:- info([
version is 1.0,
date is 1998/3/23,
author is 'Paulo Moura',
comment is 'Stack of bricks as a constrained binary relation.']).
descriptor_([top, bottom]).
domain_(top, brick).
domain_(bottom, brick).
key_([top, bottom]).
cardinality_(top, 0, 1).
cardinality_(bottom, 0, 1).
delete_option_(top, cascade).
delete_option_(bottom, restrict).
add_tuple([A, B]) :-
B::position(Xb, Yb),
Ya2 is Yb + 1,
{A::move(Xb, Ya2)},
^^add_tuple([A, B]).
activ_points_(top, before, []).
activ_points_(top, after, [move(_, _)]).
activ_points_(bottom, before, []).
activ_points_(bottom, after, [move(_, _)]).
propagate(after, move(X, Y), Top, top, [Top, Bottom]) :-
!,
Y2 is Y - 1,
(Bottom::position(X, Y2) ->
true
;
::remove_tuple([Top, Bottom])).
propagate(after, move(X, Y), Bottom, bottom, [Top, Bottom]) :-
!,
Y2 is Y + 1,
{Top::move(X, Y2)}.
:- end_object.
:- object(stack_monitor,
implements(event_handlersp)).
:- info([
version is 1.0,
date is 1998/3/23,
author is 'Paulo Moura',
comment is 'Monitor for brick movements printing an ascii representation of each brick position.']).
:- uses(loop).
:- uses(list).
after(_, move(_, _), _) :-
findall(
(Brick, X, Y),
(instantiates_class(Brick, brick), Brick::position(X, Y)),
Bricks),
setof(X, Brick^Y^ (list::member((Brick,X,Y), Bricks)), Xs),
list::last(Xs, Xmax),
setof(Y, Brick^X^ (list::member((Brick,X,Y), Bricks)), Ys),
list::last(Ys, Ymax),
loop::fordownto(Y, Ymax, 1,
(write('|'),
loop::forto(X, 1, Xmax,
(list::member((Brick, X, Y), Bricks) ->
write(Brick)
;
write('.'))),
nl)),
write('-'),
loop::forto(X, 1, Xmax, write('-')), nl.
:- end_object.
|
