fix

lib/Entity/NullableEntity.php

@@ -0,0 +1,19 @@
+<?php
+
+
+namespace Bx\Nullable\Entity;
+
+
+use Bx\Nullable\IFields\NullableFields;
+use Wt\Core\Entity\AEntity;
+
+class NullableEntity extends AEntity
+{
+    /**
+     * @return NullableFields
+     */
+    public function fields()
+    {
+        return parent::fields();
+    }
+}