1 2 // Copyright (C) 2006-2009, 2012 Alexander Nasonov 3 // Copyright (C) 2012 Lorenzo Caminiti 4 // Distributed under the Boost Software License, Version 1.0 5 // (see accompanying file LICENSE_1_0.txt or a copy at 6 // http://www.boost.org/LICENSE_1_0.txt) 7 // Home at http://www.boost.org/libs/scope_exit 8 9 #include <boost/scope_exit.hpp> 10 #include <boost/typeof/typeof.hpp> 11 #include <boost/typeof/std/vector.hpp> 12 #include BOOST_TYPEOF_INCREMENT_REGISTRATION_GROUP() 13 #include <boost/detail/lightweight_test.hpp> 14 #include <vector> 15 16 struct person {}; 17 BOOST_TYPEOF_REGISTER_TYPE(person) 18 19 template<typename Person> 20 struct world { 21 void add_person(Person const& a_person); populationworld22 size_t population(void) const { return persons_.size(); } 23 24 private: 25 std::vector<Person> persons_; 26 }; 27 BOOST_TYPEOF_REGISTER_TEMPLATE(world, 1) 28 29 template<typename Person> add_person(Person const & a_person)30void world<Person>::add_person(Person const& a_person) { 31 bool commit = false; 32 persons_.push_back(a_person); 33 34 BOOST_SCOPE_EXIT_TPL( (&commit) (this_) ) { 35 if(!commit) this_->persons_.pop_back(); 36 } BOOST_SCOPE_EXIT_END 37 38 // ... 39 40 commit = true; 41 } 42 main(void)43int main(void) { 44 world<person> w; 45 person p; 46 w.add_person(p); 47 BOOST_TEST(w.population() == 1); 48 return boost::report_errors(); 49 } 50 51