Core/Misc: Add Concepts.h from master branch

src/common/Utilities/Concepts.h

@@ -0,0 +1,29 @@
+/*
+ * 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 TRINITYCORE_CONCEPTS_H
+#define TRINITYCORE_CONCEPTS_H
+
+#include <concepts>
+
+namespace Trinity
+{
+template <typename Callable, typename R, typename... Args>
+concept invocable_r = std::is_invocable_r_v<R, Callable, Args...>;
+}
+
+#endif // TRINITYCORE_CONCEPTS_H