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diff --git a/src/id.h b/src/id.h
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+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/***************************************************************************
+ *            id.h
+ *
+ *  Sun 16 Feb 2020 04:17:19 PM CET
+ *  Copyright 2020 André Nusser
+ *  andre.nusser@googlemail.com
+ ****************************************************************************/
+
+/*
+ *  This file is part of DrumGizmo.
+ *
+ *  DrumGizmo is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU Lesser General Public License as published by
+ *  the Free Software Foundation; either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  DrumGizmo 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 Lesser General Public License for more details.
+ *
+ *  You should have received a copy of the GNU Lesser General Public License
+ *  along with DrumGizmo; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA.
+ */
+#pragma once
+
+#include <cstdint>
+#include <functional>
+#include <limits>
+
+// Typesafe ID class such that there are compiler errors if different IDs are
+// mixed. The template parameter T is just there to assure this behavior.
+// Additionally, we have a member function which can check for validity.
+template <typename T>
+struct ID
+{
+public:
+	using IDType = uint32_t;
+	static constexpr IDType invalid_value = std::numeric_limits<IDType>::max();
+
+	ID(IDType id = invalid_value) : id(id) {}
+
+	operator IDType() const { return id; }
+	IDType operator+(ID<T> other) const { return id + other.id; }
+	IDType operator+(int offset) const { return id + offset; }
+	IDType operator+(size_t offset) const { return id + offset; }
+	IDType operator-(ID<T> other) const { return id - other.id; }
+	IDType operator-(int offset) const { return id - offset; }
+	IDType operator/(int div) const { return id/div; }
+	IDType operator+=(ID<T> other) { return id += other.id; }
+	IDType operator-=(ID<T> other) { return id -= other.id; }
+	IDType operator=(ID<T> other) { return id = other.id; }
+	IDType operator++() { return ++id; }
+	IDType operator--() { return --id; }
+	bool operator!=(ID<T> other) const { return id != other.id; }
+
+	bool valid() const { return id != invalid_value; }
+	void invalidate() { id = invalid_value; }
+
+private:
+	IDType id;
+};
+
+// define custom hash function to be able to use IDs with maps/sets
+namespace std
+{
+
+template <typename T>
+struct hash<ID<T>>
+{
+	using IDType = typename ID<T>::IDType;
+	std::size_t operator()(ID<T> const& id) const noexcept
+	{
+		return std::hash<IDType>()(id);
+	}
+};
+
+} // std