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// Function library
// Copyright (C) 2001-2003 Douglas Gregor
// 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 <boost/function.hpp>
#include <iostream>
float mul_ints(int x, int y) { return ((float)x) * y; }
struct int_div {
float operator()(int x, int y) const { return ((float)x)/y; };
};
int main()
{
boost::function<float (int x, int y)> f;
f = int_div();
std::cout << f(5, 3) << std::endl;
if (f)
std::cout << f(5, 3) << std::endl;
else
std::cout << "f has no target, so it is unsafe to call" << std::endl;
f = 0;
f = &mul_ints;
return 0;
}
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