diff --git a/src/main/java/com/probejs/document/type/TypeObject.java b/src/main/java/com/probejs/document/type/TypeObject.java
index 355c60b2..6cbb6f71 100644
--- a/src/main/java/com/probejs/document/type/TypeObject.java
+++ b/src/main/java/com/probejs/document/type/TypeObject.java
@@ -44,6 +44,6 @@ public String transform(BiFunction<DocType, String, String> transformer) {
         return "{" + raw.entrySet()
             .stream()
             .map(entry -> String.format("%s: %s", entry.getKey(), entry.getValue().transform(transformer)))
-            .collect(Collectors.joining(", ")) + "}";
+            .collect(Collectors.joining("; ")) + "}";
     }
 }