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// Copyright (C) 2009-2012 Lorenzo Caminiti
// Distributed under the Boost Software License, Version 1.0
// (see accompanying file LICENSE_1_0.txt or a copy at
// http://www.boost.org/LICENSE_1_0.txt)
// Home at http://www.boost.org/libs/local_function
#include <boost/phoenix/core.hpp>
#include <boost/phoenix/function.hpp>
#include <boost/detail/lightweight_test.hpp>
//[phoenix_factorial
struct factorial_impl { // Phoenix function from global functor.
template<typename Sig>
struct result;
template<typename This, typename Arg>
struct result<This (Arg)> : result<This (Arg const&)> {};
template<typename This, typename Arg>
struct result<This (Arg&)> { typedef Arg type; };
template<typename Arg> // Polymorphic.
Arg operator()(Arg n) const {
return (n <= 0) ? 1 : n * (*this)(n - 1);
}
};
int main(void) {
using boost::phoenix::arg_names::arg1;
boost::phoenix::function<factorial_impl> factorial;
int i = 4;
BOOST_TEST(factorial(i)() == 24); // Call.
BOOST_TEST(factorial(arg1)(i) == 24); // Lazy call.
return boost::report_errors();
}
//]
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