diff --git a/core/my_basic.h b/core/my_basic.h
index aa01ccb..c56aae2 100755
--- a/core/my_basic.h
+++ b/core/my_basic.h
@@ -473,7 +473,8 @@ typedef enum mb_meta_func_u {
 	MB_MF_ADD,
 	MB_MF_SUB,
 	MB_MF_MUL,
-	MB_MF_DIV
+	MB_MF_DIV,
+	MB_MF_NEG
 } mb_meta_func_u;
 
 typedef unsigned char mb_val_bytes_t[mb_max(mb_max(sizeof(void*), sizeof(unsigned long)), mb_max(sizeof(int_t), sizeof(real_t)))];