added a test for immutable

diff --git a/Robust/src/IR/TypeDescriptor.java b/Robust/src/IR/TypeDescriptor.java
index 9c83be1ab81a1bd5230b1bfc70e7b99d3f8475e4..579b4dd5c19fe6290590625c56f4b2cb55454fd0 100644 (file)
--- a/Robust/src/IR/TypeDescriptor.java
+++ b/Robust/src/IR/TypeDescriptor.java
@@ -221,6 +221,10 @@ public class TypeDescriptor extends Descriptor {
     return type==TAG;
   }
 
+  public boolean isImmutable() {
+    return isPrimitive() || isString();
+  }
+
   public TypeDescriptor(NameDescriptor name) {
     super(name.toString());
     this.type=CLASS;