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#include <stdio.h>
#include <stdbool.h>
#include <stdlib.h>

struct animal {
        char *name;
        char *species;
};

#define class struct
typedef class animal Animal;

typedef class carnivoire {
        Animal parent;
} Carnivoire;

void animal_eats (Animal *self)
{
        printf("%s eats ???\n", self->name);
}

void carnivoire_eats (Carnivoire *self)
{
        printf("%s eats meat (a shame—it involves killing other animals)\n", self->parent.name);
}

char *animal_get_name (Animal *self)
{
        return self->name;
}
void animal_set_name (Animal *self, char *name)
{
        self->name = name;
}

typedef class feline {
        Carnivoire parent;
        bool claws_out;
} Feline;
// Don't have to define name getter/setter: animal has it already.
bool feline_get_claws_out (Feline *self)
{
        return self->claws_out;
}
void feline_protract_claws (Feline *self)
{
        self->claws_out = true;
}
void feline_retract_claws (Feline *self)
{
        self->claws_out = false;
}

typedef class cat {
        Feline parent;
} Cat;
void cat_purr (Cat *self)
{
        printf("%s purrs...\n", animal_get_name(self));
        feline_retract_claws(self);
}
void cat_eats (Cat *self)
{
        printf("%s eats mice\n", animal_get_name(self));
}

#define eats(animal)                            \
_Generic((animal),                              \
         Carnivoire *: carnivoire_eats,         \
         Cat *: cat_eats,                       \
         default: animal_eats)                  \
((animal))


int main (void)
{
        struct animal oldie = {.name = "Oldie", .species = "Miacid"};
        printf("This really old animal is %s of %s species\n", oldie.name, oldie.species);
        Carnivoire sabre_tooth = {{.name = "Diego", .species = "Dinictis"}};
        eats((Animal *)&sabre_tooth);
        eats(&sabre_tooth);
        // My little sweet boy
        Cat Kalyam = {{{{.name = "Kalyam", .species = "Felis catus"}}, .claws_out = true}};
        printf("%s's claws are %stracted\n",
               animal_get_name(&Kalyam),
               (feline_get_claws_out(&Kalyam) ? "pro" : "re"));
        eats(&Kalyam);
        cat_purr(&Kalyam);
        printf("%s's claws are %stracted\n",
               animal_get_name(&Kalyam),
               (feline_get_claws_out(&Kalyam) ? "pro" : "re"));
        return EXIT_SUCCESS;
}