| 1 | // Function library |
|---|---|
| 2 | |
| 3 | // Copyright (C) 2001-2003 Douglas Gregor |
| 4 | |
| 5 | // Use, modification and distribution is subject to the Boost Software |
| 6 | // License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at |
| 7 | // http://www.boost.org/LICENSE_1_0.txt) |
| 8 | |
| 9 | // For more information, see http://www.boost.org/ |
| 10 | |
| 11 | |
| 12 | #include <boost/function.hpp> |
| 13 | #include <iostream> |
| 14 | |
| 15 | |
| 16 | float mul_ints(int x, int y) { return ((float)x) * y; } |
| 17 | struct int_div { |
| 18 | float operator()(int x, int y) const { return ((float)x)/y; }; |
| 19 | }; |
| 20 | |
| 21 | int main() |
| 22 | { |
| 23 | boost::function<float (int x, int y)> f; |
| 24 | f = int_div(); |
| 25 | std::cout << f(5, 3) << std::endl; |
| 26 | if (f) |
| 27 | std::cout << f(5, 3) << std::endl; |
| 28 | else |
| 29 | std::cout << "f has no target, so it is unsafe to call"<< std::endl; |
| 30 | f = 0; |
| 31 | f = &mul_ints; |
| 32 | |
| 33 | return 0; |
| 34 | } |
| 35 |