mrb_fiber_yield() is available now; you have to link mruby-fiber mrbg…

…em to use the function; there's no function available to create new fiber from C (countapart of Lua's lua_newthread), but that's because you cannot create a new fiber from C due to mruby C API design limitation. define your method to create fibers in Ruby; close #1269

include/mruby.h

@@ -374,6 +374,9 @@ mrb_value mrb_attr_get(mrb_state *mrb, mrb_value obj, mrb_sym id);
 mrb_bool mrb_respond_to(mrb_state *mrb, mrb_value obj, mrb_sym mid);
 mrb_bool mrb_obj_is_instance_of(mrb_state *mrb, mrb_value obj, struct RClass* c);
 
+/* fiber functions (you need to link mruby-fiber mrbgem to use) */
+mrb_value mrb_fiber_yield(mrb_state *mrb, int argc, mrb_value *argv);
+
 /* memory pool implementation */
 typedef struct mrb_pool mrb_pool;
 struct mrb_pool* mrb_pool_open(mrb_state*);

mrbgems/mruby-fiber/src/fiber.c

@@ -205,23 +205,11 @@ fiber_alive_p(mrb_state *mrb, mrb_value self)
   return mrb_bool_value(c->status != MRB_FIBER_TERMINATED);
 }
 
-/*
- *  call-seq:
- *     Fiber.yield(args, ...) -> obj
- *
- *  Yields control back to the context that resumed the fiber, passing
- *  along any arguments that were passed to it. The fiber will resume
- *  processing at this point when <code>resume</code> is called next.
- *  Any arguments passed to the next <code>resume</code> will be the
- *  value that this <code>Fiber.yield</code> expression evaluates to.
- */
-static mrb_value
-fiber_yield(mrb_state *mrb, mrb_value self)
+mrb_value
+mrb_fiber_yield(mrb_state *mrb, int len, mrb_value *a)
 {
   struct mrb_context *c = mrb->c;
   mrb_callinfo *ci;
-  mrb_value *a;
-  int len;
 
   for (ci = c->ci; ci >= c->cibase; ci--) {
     if (ci->acc < 0) {
@@ -231,14 +219,34 @@ fiber_yield(mrb_state *mrb, mrb_value self)
   if (!c->prev) {
     mrb_raise(mrb, E_ARGUMENT_ERROR, "can't yield from root fiber");
   }
-  mrb_get_args(mrb, "*", &a, &len);
+
   c->prev->status = MRB_FIBER_RUNNING;
   mrb->c = c->prev;
   c->prev = NULL;
   MARK_CONTEXT_MODIFY(mrb->c);
   return fiber_result(mrb, a, len);
 }
 
+/*
+ *  call-seq:
+ *     Fiber.yield(args, ...) -> obj
+ *
+ *  Yields control back to the context that resumed the fiber, passing
+ *  along any arguments that were passed to it. The fiber will resume
+ *  processing at this point when <code>resume</code> is called next.
+ *  Any arguments passed to the next <code>resume</code> will be the
+ *  value that this <code>Fiber.yield</code> expression evaluates to.
+ */
+static mrb_value
+fiber_yield(mrb_state *mrb, mrb_value self)
+{
+  mrb_value *a;
+  int len;
+
+  mrb_get_args(mrb, "*", &a, &len);
+  return mrb_fiber_yield(mrb, len, a);
+}
+
 /*
  *  call-seq:
  *     Fiber.current() -> fiber