diff -r 28294b895e5e -r 68a281aefa76 src/lib/ProxyVector.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/lib/ProxyVector.h	Sat Jul 24 17:35:27 2021 +0200
@@ -0,0 +1,47 @@
+/**
+ * Relational pipes
+ * Copyright © 2021 František Kučera (Frantovo.cz, GlobalCode.info)
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, version 3 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+#pragma once
+
+#include <memory>
+
+namespace relpipe {
+namespace in {
+namespace asn1 {
+namespace lib {
+
+template <typename Class>
+class ProxyVector : public std::vector<std::shared_ptr<Class>> {
+public:
+
+	/**
+	 * Call given method on all instances.
+	 *
+	 * @param method a method of Class
+	 * @param arguments arguments of the method
+	 */
+	template<typename Method, typename... Arguments> void forward(Method method, Arguments&&... arguments) {
+		for (auto& h : * this) {
+			// TODO: optionally handle/collect exceptions
+			(h.get()->*method)(arguments...);
+		}
+	}
+};
+
+}
+}
+}
+}