Copyright (C) 2012-2020 Rudolf Cardinal (firstname.lastname@example.org).
This file is part of CamCOPS.
CamCOPS 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 3 of the License, or
(at your option) any later version.
CamCOPS 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 CamCOPS. If not, see <http://www.gnu.org/licenses/>.
// Class to set a boolean flag to true during the lifetime of this
// object, then restores it again on destruction.
// (Use e.g. for functions having multiple exit points where you want a
// flag saying "I am in this function" to prevent infinite recursion.)
// See also ReentryDepthGuard.
bool previousState() const;