x = 20; $c->y = 30; $s->x = -10; $s->y = 5; print "\nHere is their current position:\n"; print " Circle = ({$c->x},{$c->y})\n"; print " Square = ({$s->x},{$s->y})\n"; # ----- Call some methods ----- # Notice how the Shape_area() and Shape_perimeter() functions really # invoke the appropriate virtual method on each object. print "\nHere are some properties of the shapes:\n"; foreach (array($c,$s) as $o) { print " ". get_class($o) . "\n"; print " area = {$o->area()}\n"; print " perimeter = {$o->perimeter()}\n"; } # ----- Delete everything ----- print "\nGuess I'll clean up now\n"; # Note: this invokes the virtual destructor $c = NULL; $s = NULL; # and don't forget the $o from the for loop above. It still refers to # the square. $o = NULL; print Shape::get_nshapes() . " shapes remain\n"; print "Goodbye\n"; ?>