From cfb95aa71448e829e40c1a42d83fa2fa28a816c5 Mon Sep 17 00:00:00 2001
From: Marco Feder <marco.feder@sissa.it>
Date: Tue, 11 Jul 2023 21:03:31 +0200
Subject: [PATCH] Forward declarations for ArborXWrappers

---
 source/grid/grid_tools.cc | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/source/grid/grid_tools.cc b/source/grid/grid_tools.cc
index 6f4476bc47..e480638fd6 100644
--- a/source/grid/grid_tools.cc
+++ b/source/grid/grid_tools.cc
@@ -23,6 +23,19 @@
 #ifdef DEAL_II_WITH_ARBORX
 #  include <deal.II/arborx/access_traits.h>
 #  include <deal.II/arborx/distributed_tree.h>
+#else
+namespace ArborXWrappers
+{
+  class DistributedTree
+  {
+  public:
+    template <typename QueryType>
+    std::pair<std::vector<std::pair<int, int>>, std::vector<int>>
+    query(const QueryType &queries);
+  };
+  class BoundingBoxIntersectPredicate
+  {};
+} // namespace ArborXWrappers
 #endif
 
 #ifdef DEAL_II_WITH_CGAL
-- 
2.39.5