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/*
* Copyright (C) 2001-2019 Jacek Sieka, arnetheduck on gmail point com
*
* 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 <https://www.gnu.org/licenses/>.
*/
#pragma once
namespace dcpp {
/* helper class to run a functor when the object goes out of scope.
the additional #defines generate a unique object name thanks to the __COUNTER__ macro.
for example, the call:
ScopedFunctor([] { printf("hello"); });
will print "hello" when the current scope ends. */
template<typename F>
struct ScopedFunctor {
explicit ScopedFunctor(F f_) : f(f_) { }
~ScopedFunctor() { f(); }
private:
F f;
};
template<typename F>
ScopedFunctor<F> makeScopedFunctor(F f) { return ScopedFunctor<F>(f); }
#define ScopedFunctor_gen(ScopedFunctor_name, ScopedFunctor_counter) ScopedFunctor_name##ScopedFunctor_counter
#define ScopedFunctor_(ScopedFunctor_f, ScopedFunctor_counter) \
auto ScopedFunctor_gen(ScopedFunctor_object, ScopedFunctor_counter) = makeScopedFunctor(ScopedFunctor_f)
#define ScopedFunctor(ScopedFunctor_f) ScopedFunctor_(ScopedFunctor_f, __COUNTER__)
} // namespace dcpp
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