demos/objects/objects-wiki.c

   1 #include <cll1.h>
   2
   3 /* This is C<<1 rewrite of object polymorphism from
   4    http://en.wikipedia.org/wiki/Polymorphism_in_object-oriented_programming */
   5
   6 struct Animal
   7 {
   8  use_interface(AnimalActions);
   9  char *name;
  10 };
  11
  12 struct AnimalActions
  13 {
  14  const char *(method(talk));
  15 }
  16
  17 struct *Animal get_animal(char *name, struct AnimalActions *interface)
  18 {
  19  struct *Animal animal=get_object(Animal,interface);
  20  animal->name=name;
  21  return animal;
  22 }
  23
  24 const char *cat_talk(void *_self)
  25 {
  26  return "Meow!";
  27 }
  28
  29 const char *dog_talk(void *_self)
  30 {
  31  return "Arf! Arf!";
  32 }
  33
  34 interface_implementation(CatActions,AnimalActions)
  35 {
  36  bind_method(talk,cat_talk);
  37 }
  38
  39 interface_implementation(DogActions,AnimalActions)
  40 {
  41  bind_method(talk,dog_talk);
  42 }
  43
  44 program
  45 {
  46  int i;
  47  struct Animals *animal[3];
  48  struct AnimalActions *cat = get_interface(CatActions);
  49  struct AnimalActions *dog = get_interface(DogActions);
  50
  51  animal[0]=get_animal("Missy",cat);
  52  animal[0]=get_animal("Mr. Bojangles",cat);
  53  animal[0]=get_animal("Lassie",dog);
  54
  55  for_range(i,0,2)
  56   printf("%s: %s\n",animal[i].name,(_(animal[i],talk)));
  57
  58 }