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|
=================================================================
Logtalk - Object oriented extension to Prolog
Release 2.27.1
Copyright (c) 1998-2006 Paulo Moura. All Rights Reserved.
=================================================================
% start by loading the necessary library and support example files (if not
% already loaded):
| ?- logtalk_load([library(events_loader), library(types_loader), library(metapredicates_loader), library(hierarchies_loader)]).
...
| ?- logtalk_load(roots(loader)).
...
| ?- logtalk_load(relations(loader)).
...
% now you are ready for loading the example:
| ?- logtalk_load(points(loader)).
...
% let's start with a simple point:
| ?- point::new(Point,[position-(1, 3)]), Point::(print, move(7, 4), print).
p1 @ (1, 3)
p1 @ (7, 4)
Point = p1 ?
yes
% same problem but with bounds on coordinate values:
| ?- bounded_point::new(Point,[position-(1, 3), bounds(x)-(0, 13), bounds(y)-(-7, 7)]), Point::(print, move(7, 4), print).
bounds(x) : 0,13
bounds(y) : -7,7
bp2 @ (1, 3)
bounds(x) : 0,13
bounds(y) : -7,7
bp2 @ (7, 4)
Point = bp2 ?
yes
% same problem but storing the history of coordinate values:
| ?- history_point::new(Point,[position-(1, 3)]), Point::(print, move(7, 4), print).
location history: []
hp3 @ (1, 3)
location history: [(1,3)]
hp3 @ (7, 4)
Point = hp3 ?
yes
% same problem but with bounds on coordinate values and storing past values:
| ?- bounded_history_point::new(Point,[position-(1, 3), bounds(x)-(0, 13), bounds(y)-(-7, 7)]), Point::(print, move(7, 4), print).
bounds(x) : 0,13
bounds(y) : -7,7
location history: []
bhp4 @ (1, 3)
bounds(x) : 0,13
bounds(y) : -7,7
location history: [(1,3)]
bhp4 @ (7, 4)
Point = bhp4 ?
yes
% clean up instances:
| ?- (point, bounded_point, history_point, bounded_history_point)::delete_all.
yes
|
