diff --git a/src/src_tree.rs b/src/src_tree.rs
index 2c15594..96e0111 100644
--- a/src/src_tree.rs
+++ b/src/src_tree.rs
@@ -418,7 +418,7 @@ impl SrcTree {
             "get",
             "not-contains",
             "contains",
-            "set-uniton",
+            "set-union",
             "set-diff",
             "set-intersect",
             "map-remove",