diff --git a/src/object.c b/src/object.c
index 777fd27..0fd82ad 100644
--- a/src/object.c
+++ b/src/object.c
@@ -119,6 +119,14 @@ cfw_free(void *ptr)
 	free(obj);
 }
 
+bool
+cfw_is(void *ptr, CFWClass *cls)
+{
+	CFWObject *obj = ptr;
+
+	return (obj->cls == cls);
+}
+
 bool
 cfw_equal(void *ptr1, void *ptr2)
 {
diff --git a/src/object.h b/src/object.h
index 5afdc42..d309f29 100644
--- a/src/object.h
+++ b/src/object.h
@@ -40,6 +40,7 @@ extern void* cfw_new_p(CFWClass*, ...);
 extern void* cfw_ref(void*);
 extern void cfw_unref(void*);
 extern void cfw_free(void*);
+extern bool cfw_is(void*, CFWClass*);
 extern bool cfw_equal(void*, void*);
 extern uint32_t cfw_hash(void*);
 extern void* cfw_copy(void*);