diff --git a/list-type.go b/list-type.go
index ce12731..4afb960 100644
--- a/list-type.go
+++ b/list-type.go
@@ -106,16 +106,16 @@ func (ls *ListType) TypeName() string {
 	return "list"
 }
 
-func (list *ListType) indexDeepCmp(target any) (index int) {
-	index = -1
-	for i, item := range *list {
-		if reflect.DeepEqual(item, target) {
-			index = i
-			break
-		}
-	}
-	return
-}
+// func (list *ListType) indexDeepCmp(target any) (index int) {
+// 	index = -1
+// 	for i, item := range *list {
+// 		if reflect.DeepEqual(item, target) {
+// 			index = i
+// 			break
+// 		}
+// 	}
+// 	return
+// }
 
 func (ls *ListType) contains(t *ListType) (answer bool) {
 	if len(*ls) >= len(*t) {