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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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