diff --git a/Parser/spec/Helpers.jadd b/Parser/spec/Helpers.jadd
new file mode 100644
index 0000000000000000000000000000000000000000..a147c4b4caed0bb36b1d108deb12255f2db3698e
--- /dev/null
+++ b/Parser/spec/Helpers.jadd
@@ -0,0 +1,22 @@
+aspect Helpers {
+
+    public void ASTNode.checkTreeStructure() {
+        for (ASTNode child : astChildren()) {
+            if (child.getParent() != this) {
+                throw new RuntimeException();
+            }
+            child.checkTreeStructure();
+        }
+    }
+
+    public void ASTNode.fixTreeStructure() {
+        for (ASTNode child : astChildren()) {
+            if (child.getParent() != this) {
+                // System.err.println("fixed parent of " + child);
+                child.parent = this;
+            }
+            child.fixTreeStructure();
+        }
+    }
+
+}