From c8357c8a139de23cd7c9b31d83ff6ec08655e61e Mon Sep 17 00:00:00 2001
From: Grahame Grieve <grahameg@gmail.ccom>
Date: Fri, 20 Oct 2023 16:28:34 +1100
Subject: [PATCH] fix for NPE building sql-on-fhir

---
 .../src/main/java/org/hl7/fhir/r5/model/ExpressionNode.java   | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/org.hl7.fhir.r5/src/main/java/org/hl7/fhir/r5/model/ExpressionNode.java b/org.hl7.fhir.r5/src/main/java/org/hl7/fhir/r5/model/ExpressionNode.java
index bc005910b..0742ef2e9 100644
--- a/org.hl7.fhir.r5/src/main/java/org/hl7/fhir/r5/model/ExpressionNode.java
+++ b/org.hl7.fhir.r5/src/main/java/org/hl7/fhir/r5/model/ExpressionNode.java
@@ -721,9 +721,9 @@ public class ExpressionNode {
     } else if (group != null) {
       names.addAll(group.getDistalNames());
     } else if (function != null) {
-      names.addAll(null);
+      names.add(null);
     } else if (constant != null) {
-      names.addAll(null);
+      names.add(null);
     } else {
       names.add(name);
     }