3 files changed, 73 insertions, 50 deletions

diff --git a/include/stc/algo/ccoro.h b/include/stc/algo/ccoro.h
index f5c682e8..07f98bf4 100644
--- a/include/stc/algo/ccoro.h
+++ b/include/stc/algo/ccoro.h
@@ -67,20 +67,21 @@ int main(void) {
      } \
      *_state = -2
 
-#define ccoro_yield(...)  c_MACRO_OVERLOAD(ccoro_yield, __VA_ARGS__)
-#define ccoro_yield_1(value) \
+#define ccoro_yield(ret) \
     do { \
-        *_state = __LINE__; return value; \
+        *_state = __LINE__; return ret; \
         case __LINE__:; \
     } while (0)
 
-#define ccoro_yield_2(subcoro, c) \
+#define ccoro_yield_call(...)  c_MACRO_OVERLOAD(ccoro_yield_call, __VA_ARGS__)
+#define ccoro_yield_call_2(c, subcoro) ccoro_yield_call_3(c, subcoro, )
+#define ccoro_yield_call_3(c, subcoro, ret) \
     do { \
         *_state = __LINE__; \
-        c_PASTE(coro, __LINE__): \
-        return subcoro; \
+        c_PASTE(co, __LINE__): \
+        subcoro; return ret; \
         case __LINE__:; \
-        if (ccoro_alive(c)) goto c_PASTE(coro, __LINE__); \
+        if (ccoro_alive(c)) goto c_PASTE(co, __LINE__); \
     } while (0)
 
 #define ccoro_final case -1
diff --git a/misc/examples/cofib.c b/misc/examples/cofib.c
deleted file mode 100644
index b58775ae..00000000
--- a/misc/examples/cofib.c
+++ /dev/null
@@ -1,43 +0,0 @@
-#include <stc/algo/ccoro.h>
-#include <stdio.h>
-#include <stdint.h>
-
-// Use coroutine to create a fibonacci sequence generator:
-
-typedef long long llong;
-struct fibonacci {
-    int n; 
-    int ccoro_state;
-    llong a, b, idx;
-};
-
-llong fibonacci(struct fibonacci* U) {
-    assert (U->n < 95);
-
-    ccoro_execute(U,
-        U->a = 0;
-        U->b = 1;
-        for (U->idx = 0; U->idx < U->n; U->idx++) {
-            ccoro_yield (U->a);
-            llong sum = U->a + U->b; // NB! locals only lasts until next ccoro_yield!
-            U->a = U->b;
-            U->b = sum;
-        }
-        ccoro_final:
-    );
-
-    return -1;
-}
-
-
-int main(void) {
-    printf("Fibonacci numbers:\n");
-    struct fibonacci fib = {.n = 14};
-
-    for (;;) {
-       llong x = fibonacci(&fib);
-       if (!ccoro_alive(&fib)) break;
-       printf(" %lld", x);
-    }
-    puts("");
-}
diff --git a/misc/examples/cosub.c b/misc/examples/cosub.c
new file mode 100644
index 00000000..0aee7aee
--- /dev/null
+++ b/misc/examples/cosub.c
@@ -0,0 +1,65 @@
+#include <stc/algo/ccoro.h>
+#include <stdio.h>
+#include <stdint.h>
+
+// Use coroutine to create a fibonacci sequence generator:
+
+typedef long long intll_t;
+
+struct fibonacci {
+    int n; 
+    int ccoro_state;
+    intll_t a, b, idx;
+};
+
+intll_t fibonacci(struct fibonacci* F) {
+    assert (F->n < 95);
+
+    ccoro_execute(F,
+        F->a = 0;
+        F->b = 1;
+        for (F->idx = 0; F->idx < F->n; F->idx++) {
+            ccoro_yield (F->a);
+            intll_t sum = F->a + F->b; // NB! locals only lasts until next ccoro_yield!
+            F->a = F->b;
+            F->b = sum;
+        }
+        ccoro_final:
+    );
+
+    return -1;
+}
+
+// Demonstrate to call another coroutine from a coroutine:
+// Create a 2D iterator, and call fibonacci sequence when x,y = 1,1:
+
+struct iterate {
+    int max_x, max_y; 
+    int ccoro_state; 
+    int x, y;
+};
+
+bool iterate(struct iterate* I, struct fibonacci* F) {
+    ccoro_execute(I,
+        for (I->x = 0; I->x < I->max_x; I->x++)
+            for (I->y = 0; I->y < I->max_y; I->y++)
+                if (I->x == 1 && I->y == 1)
+                    ccoro_yield_call (F, fibonacci(F), true);
+                else
+                    ccoro_yield (true);
+        ccoro_finish:
+    );
+    return false;
+}
+
+
+int main(void) {
+    printf("Fibonacci numbers:\n");
+    struct fibonacci fib = {.n = 14};
+    struct iterate iter = {3, 3};
+
+    while (iterate(&iter, &fib))
+        printf("%d %d. Fib: %lld\n", iter.x, iter.y, fib.a);
+
+    puts("");
+}