Create Objects and Methods of Objects in C

Object Oriented C

#include <stdio.h>
#include <assert.h>

/* #include "New.h"
#include "Object.h"
#include "Set.h" */

#if ! defined MANY || MANY < 1
#define MANY 10
#endif
static int heap [MANY];

void * new (const void * type, ...)
{ int * p; /* & heap[1..] */
for (p = heap + 1; p < heap + MANY; ++ p)
if (! * p)
break;
assert(p < heap + MANY);
* p = MANY;
return p;
}

void delete (void * _item) { 
 int * item = _item;
 if (item) { 
 assert(item > heap && item < heap + MANY);
 * item = 0;
 }
}

void * add (void * _set, const void * _element) { 
int * set = _set;
const int * element = _element;
assert(set > heap && set < heap + MANY);
assert(* set == MANY);
assert(element > heap && element < heap + MANY);
if (* element == MANY)
*(int *) element = set - heap;
else
assert(* element == set - heap);
return (void *) element;
}

void * find (const void * _set, const void * _element) { 
const int * set = _set;
const int * element = _element;
assert(set > heap && set < heap + MANY);
assert(* set == MANY);
assert(element > heap && element < heap + MANY);
assert(* element);
return * element == set - heap ? (void *) element : 0;
}

int contains (const void * _set, const void * _element) {
return find(_set, _element) != 0;
}

void * drop (void * _set, const void * _element) { 
int * element = find(_set, _element);
if (element)
* element = MANY;
return element;
}

int differ (const void * a, const void * b)
{
return a != b;
}

const void * Set;
const void * Object;

int main () { 

void * new (const void * type, ...);
void delete (void * item);


extern const void * Set;
void * add (void * set, const void * element);
void * find (const void * set, const void * element);
void * drop (void * set, const void * element);
int contains (const void * set, const void * element);

extern const void * Object; /* new(Object); */
int differ (const void * a, const void * b);



    void * s = new(Set);
    void * a = add(s, new(Object));
    void * b = add(s, new(Object));
    void * c = new(Object);

if (contains(s, a) && contains(s, b))
puts("ok");
if (contains(s, c))
puts("contains?");
if (differ(a, add(s, a)))
puts("differ?");
if (contains(s, drop(s, a)))
puts("drop?");

delete(drop(s, b));
delete(drop(s, c));


return 0;
}