Core/PacketIO: Add a validating string helper class for use in packet classes

(cherry picked from commit f2f47f774f)

src/common/Utilities/Tuples.h

@@ -0,0 +1,34 @@
+/*
+ * This file is part of the TrinityCore Project. See AUTHORS file for Copyright information
+ *
+ * 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; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ * 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/>.
+ */
+
+#ifndef Tuples_h__
+#define Tuples_h__
+
+#include <tuple>
+
+namespace Trinity
+{
+    template <typename T, typename Tuple>
+    struct has_type;
+
+    template <typename T, typename... Us>
+    struct has_type<T, std::tuple<Us...>> : std::disjunction<std::is_same<T, Us>...>
+    {
+    };
+}
+
+#endif // Tuples_h__