Adapton programming model & Lazy evaluation - int values

adapton.c

// Reference: http://plum-umd.github.io/adapton/

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

typedef struct Adapton_Int {
  int value;
  int (*compute)(struct Adapton_Int *, struct Adapton_Int *);
  struct Adapton_Int *arg1;
  struct Adapton_Int *arg2;
} Adapton_Int;

int force(Adapton_Int *adapton_int) {
  if (adapton_int->compute == NULL) {
    return adapton_int->value;
  } else {
    adapton_int->value =
        adapton_int->compute(adapton_int->arg1, adapton_int->arg2);
    adapton_int->compute = NULL;
    return adapton_int->value;
  }
}

int add(Adapton_Int *a, Adapton_Int *b) { return force(a) + force(b); }

Adapton_Int *makeAdaptonInt(int value) {
  Adapton_Int *adapton_int = (Adapton_Int *)malloc(sizeof(Adapton_Int));
  adapton_int->value = value;
  adapton_int->compute = NULL;
  adapton_int->arg1 = NULL;
  adapton_int->arg2 = NULL;
  return adapton_int;
}

Adapton_Int *adapt(int value) {
  Adapton_Int *adapton_int = makeAdaptonInt(value);
  adapton_int->compute = NULL;
  return adapton_int;
}

Adapton_Int *makeCompute(Adapton_Int *a, Adapton_Int *b,
                         int (*computeFunc)(Adapton_Int *, Adapton_Int *)) {
  Adapton_Int *adapton_int = makeAdaptonInt(0);
  adapton_int->value = 0;
  adapton_int->compute = computeFunc;
  adapton_int->arg1 = a;
  adapton_int->arg2 = b;
  return adapton_int;
}

int main() {
  Adapton_Int *x = adapt(1);
  Adapton_Int *y = adapt(2);
  Adapton_Int *z = makeCompute(x, y, &add);
  printf("%d\n", force(z));
  x = adapt(5);
  z = makeCompute(x, y, &add);
  printf("%d\n", force(z));
  y = adapt(4);
  z = makeCompute(x, y, &add);
  printf("%d\n", force(z));
  return 0;
}

lazyint.c

#include <stdio.h>

typedef struct LazyInt {
  int value;
  int (*func)(struct LazyInt *, struct LazyInt *);
  struct LazyInt *arg1;
  struct LazyInt *arg2;
} LazyInt;

int force(LazyInt *lazyInt) {
  if (lazyInt->func == NULL) {
    return lazyInt->value;
  } else {
    lazyInt->value = lazyInt->func(lazyInt->arg1, lazyInt->arg2);
    lazyInt->func = NULL;
    return lazyInt->value;
  }
}

int add(LazyInt *a, LazyInt *b) { return force(a) + force(b); }

LazyInt lazy(int value) {
  LazyInt lazyInt;
  lazyInt.value = value;
  lazyInt.func = NULL;
  lazyInt.arg1 = NULL;
  lazyInt.arg2 = NULL;
  return lazyInt;
}

LazyInt compute(LazyInt a, LazyInt b, int (*func)(LazyInt *, LazyInt *)) {
  LazyInt lazyInt;
  lazyInt.value = 0;
  lazyInt.func = func;
  lazyInt.arg1 = &a;
  lazyInt.arg2 = &b;
  return lazyInt;
}

int main() {
  LazyInt x = lazy(1);
  LazyInt y = lazy(2);
  LazyInt z = compute(x, y, &add);
  printf("%d\n", force(&z));
  x = lazy(5);
  z = compute(x, y, &add);
  printf("%d\n", force(&z));
  y = lazy(4);
  z = compute(x, y, &add);
  printf("%d\n", force(&z));
  return 0;
}