| // 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 <algorithm> |
| #include <iostream> |
| #include <boost/signals/signal2.hpp> |
| |
| template<typename T> |
| struct maximum { |
| typedef T result_type; |
| |
| template<typename InputIterator> |
| T operator()(InputIterator first, InputIterator last) const |
| { |
| if (first == last) |
| throw std::runtime_error("Cannot compute maximum of zero elements!"); |
| return *std::max_element(first, last); |
| } |
| }; |
| |
| int main() |
| { |
| boost::signal2<int, int, int, maximum<int> > sig_max; |
| sig_max.connect(std::plus<int>()); |
| sig_max.connect(std::multiplies<int>()); |
| sig_max.connect(std::minus<int>()); |
| sig_max.connect(std::divides<int>()); |
| |
| std::cout << sig_max(5, 3) << std::endl; // prints 15 |
| |
| return 0; |
| } |