diff --git a/m-core.h b/m-core.h
index 40c125d5..5bfb7986 100644
--- a/m-core.h
+++ b/m-core.h
@@ -2143,10 +2143,11 @@ m_core_hash (const void *str, size_t length)
 // 5b. Define with arguments ==> use INIT_SET (INIT_WITH support pending)
 #define M_LETI_SINGLE2_SET(cont, oplist, name, ...)                     \
   for(M_GET_TYPE oplist name;                                           \
-      cont && (M_GET_INIT_SET oplist (name, __VA_ARGS__), true);        \
+      cont && (M_LETI_SINGLE2_INIT(oplist, name, __VA_ARGS__), true);   \
       (M_GET_CLEAR oplist (name), cont = false))                        \
     for(;cont;cont = false)
-
+#define M_LETI_SINGLE2_INIT(oplist, name, ...)                          \
+  M_IF_METHOD(INIT_WITH,oplist)(M_GET_INIT_WITH oplist (name, __VA_ARGS__), M_GET_INIT_SET oplist (name, __VA_ARGS__))
 
 /* Transform the va list by adding their number as the first argument of
    the list.
diff --git a/tests/test-mcore.c b/tests/test-mcore.c
index 09350a76..d4b6b224 100644
--- a/tests/test-mcore.c
+++ b/tests/test-mcore.c
@@ -171,14 +171,20 @@ static void test_map(void)
 
 static void test_let(void)
 {
+  bool b = false;
   M_LET(z, M_CLASSIC_OPLIST(testobj)) {
-    testobj_add(z,z,z);
+    testobj_set_ui(z, 12);
     M_LET((zz,z), M_CLASSIC_OPLIST(testobj)) {
-      testobj_add(zz,zz,z);
+      assert( testobj_cmp_ui(zz, 12) == 0);
     }
+    M_LET((zz,42), M_OPEXTEND(M_CLASSIC_OPLIST(testobj), INIT_WITH(testobj_init_set_ui))) {
+      assert( testobj_cmp_ui(zz, 42) == 0);
+    }
+    b = true;
     break;
     assert(0);
   }
+  assert(b);
 }
 
 static void test_va(void)