1 files changed, 46 insertions, 0 deletions
diff --git a/include/o3tl/optional.hxx b/include/o3tl/optional.hxx
new file mode 100644
index 000000000000..6da85698c2d8
--- /dev/null
+++ b/include/o3tl/optional.hxx
@@ -0,0 +1,46 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4; fill-column: 100 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+// A wrapper selecting either std::optional or boost::optional as a fallback for Xcode < 10.  To be
+// removed once std::optional is available everywhere.
+
+#ifndef INCLUDED_O3TL_OPTIONAL_HXX
+#define INCLUDED_O3TL_OPTIONAL_HXX
+
+#include <sal/config.h>
+
+#if defined __APPLE__ && !__has_include(<optional>)
+
+#include <boost/none.hpp>
+#include <boost/optional.hpp>
+
+namespace o3tl
+{
+using boost::make_optional;
+using boost::optional;
+
+inline constexpr auto nullopt = boost::none;
+}
+
+#else
+
+#include <optional>
+
+namespace o3tl
+{
+using std::make_optional;
+using std::nullopt;
+using std::optional;
+}
+
+#endif
+
+#endif
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab cinoptions=b1,g0,N-s cinkeys+=0=break: */