| // Boost.Signals library |
| |
| // Copyright Douglas Gregor 2001-2003. Use, modification and |
| // distribution is subject to the Boost Software License, Version |
| // 1.0. (See accompanying file LICENSE_1_0.txt or copy at |
| // http://www.boost.org/LICENSE_1_0.txt) |
| |
| // For more information, see http://www.boost.org |
| |
| #include <iostream> |
| #include <boost/signals/signal2.hpp> |
| #include <cassert> |
| |
| struct print_sum { |
| void operator()(int x, int y) const { std::cout << x+y << std::endl; } |
| }; |
| |
| struct print_product { |
| void operator()(int x, int y) const { std::cout << x*y << std::endl; } |
| }; |
| |
| struct print_difference { |
| void operator()(int x, int y) const { std::cout << x-y << std::endl; } |
| }; |
| |
| struct print_quotient { |
| void operator()(int x, int y) const { std::cout << x/-y << std::endl; } |
| }; |
| |
| |
| int main() |
| { |
| boost::signal2<void, int, int> sig; |
| |
| sig.connect(print_sum()); |
| sig.connect(print_product()); |
| |
| sig(3, 5); |
| |
| boost::signals::connection print_diff_con = sig.connect(print_difference()); |
| |
| // sig is still connected to print_diff_con |
| assert(print_diff_con.connected()); |
| |
| sig(5, 3); // prints 8, 15, and 2 |
| |
| print_diff_con.disconnect(); // disconnect the print_difference slot |
| |
| sig(5, 3); // now prints 8 and 15, but not the difference |
| |
| assert(!print_diff_con.connected()); // not connected any more |
| |
| { |
| boost::signals::scoped_connection c = sig.connect(print_quotient()); |
| sig(5, 3); // prints 8, 15, and 1 |
| } // c falls out of scope, so sig and print_quotient are disconnected |
| |
| sig(5, 3); // prints 8 and 15 |
| |
| return 0; |
| } |