1 files changed, 60 insertions, 0 deletions
diff --git a/src/qmldom/qqmldomfunctionref_p.h b/src/qmldom/qqmldomfunctionref_p.h
new file mode 100644
index 0000000000..525178e841
--- /dev/null
+++ b/src/qmldom/qqmldomfunctionref_p.h
@@ -0,0 +1,60 @@
+// Copyright (C) 2021 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
+
+#ifndef QQMLDOMFUNCTIONREF_P_H
+#define QQMLDOMFUNCTIONREF_P_H
+
+//
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the Qt API.  It exists purely as an
+// implementation detail.  This header file may change from version to
+// version without notice, or even be removed.
+//
+// We mean it.
+//
+
+#include <QtCore/private/qglobal_p.h>
+
+#if !defined(Q_CC_MSVC) || Q_CC_MSVC >= 1930
+#include <QtCore/qxpfunctional.h>
+
+QT_BEGIN_NAMESPACE
+namespace QQmlJS {
+namespace Dom {
+template <typename T>
+using function_ref = qxp::function_ref<T>;
+} // namespace Dom
+} // namespace QQmlJS
+QT_END_NAMESPACE
+
+#else
+
+#include <functional>
+
+QT_BEGIN_NAMESPACE
+namespace QQmlJS {
+namespace Dom {
+namespace _detail {
+template <typename T>
+struct function_ref_helper { using type = std::function<T>; };
+// std::function doesn't grok the const in <int(int) const>, so remove:
+template <typename R, typename...Args>
+struct function_ref_helper<R(Args...) const> : function_ref_helper<R(Args...)> {};
+// std::function doesn't grok the noexcept in <int(int) noexcept>, so remove:
+template <typename R, typename...Args>
+struct function_ref_helper<R(Args...) noexcept> : function_ref_helper<R(Args...)> {};
+// and both together:
+template <typename R, typename...Args>
+struct function_ref_helper<R(Args...) const noexcept> : function_ref_helper<R(Args...)> {};
+} // namespace _detail
+template <typename T>
+using function_ref = const typename _detail::function_ref_helper<T>::type &;
+} // namespace Dom
+} // namespace QQmlJS
+QT_END_NAMESPACE
+
+#endif
+
+#endif // QQMLDOMFUNCTIONREF_P_H