/* * Bittorrent Client using Qt and libtorrent. * Copyright (C) 2015 Vladimir Golovnev * * 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, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. * * In addition, as a special exception, the copyright holders give permission to * link this program with the OpenSSL project's "OpenSSL" library (or with * modified versions of it that use the same license as the "OpenSSL" library), * and distribute the linked executables. You must obey the GNU General Public * License in all respects for all of the code used other than "OpenSSL". If you * modify file(s), you may extend this exception to your version of the file(s), * but you are not obligated to do so. If you do not wish to do so, delete this * exception statement from your version. */ #pragma once class TriStateBool { public: static const TriStateBool Undefined; static const TriStateBool False; static const TriStateBool True; constexpr TriStateBool() = default; constexpr TriStateBool(const TriStateBool &other) = default; explicit constexpr TriStateBool(const bool boolean) { *this = boolean ? True : False; } TriStateBool &operator=(const TriStateBool &other) = default; // TODO: add constexpr when using C++17 explicit constexpr operator signed char() const { return m_value; } constexpr friend bool operator==(const TriStateBool &left, const TriStateBool &right) { return (left.m_value == right.m_value); } private: explicit constexpr TriStateBool(const int value) : m_value((value < 0) ? -1 : ((value > 0) ? 1 : 0)) { } signed char m_value = -1; // Undefined by default }; constexpr bool operator!=(const TriStateBool &left, const TriStateBool &right) { return !(left == right); }