py: Add MP_OBJ_STOP_ITERATION and make good use of it.

Also make consistent use of MP_OBJ_NOT_SUPPORTED and MP_OBJ_NULL.
This helps a lot in debugging and understanding of function API.

1 files changed, 2 insertions, 2 deletions

diff --git a/py/runtime.h b/py/runtime.h
index 6d49e49b7b..3297a21a34 100644
--- a/py/runtime.h
+++ b/py/runtime.h
@@ -50,8 +50,8 @@ void mp_load_method_maybe(mp_obj_t base, qstr attr, mp_obj_t *dest);
 void mp_store_attr(mp_obj_t base, qstr attr, mp_obj_t val);
 
 mp_obj_t mp_getiter(mp_obj_t o);
-mp_obj_t mp_iternext_allow_raise(mp_obj_t o); // may return MP_OBJ_NULL instead of raising StopIteration()
-mp_obj_t mp_iternext(mp_obj_t o); // will always return MP_OBJ_NULL instead of raising StopIteration(...)
+mp_obj_t mp_iternext_allow_raise(mp_obj_t o); // may return MP_OBJ_STOP_ITERATION instead of raising StopIteration()
+mp_obj_t mp_iternext(mp_obj_t o); // will always return MP_OBJ_STOP_ITERATION instead of raising StopIteration(...)
 mp_vm_return_kind_t mp_resume(mp_obj_t self_in, mp_obj_t send_value, mp_obj_t throw_value, mp_obj_t *ret_val);
 
 mp_obj_t mp_make_raise_obj(mp_obj_t o);