1 
2 // Copyright (C) 2009-2012 Lorenzo Caminiti
3 // Distributed under the Boost Software License, Version 1.0
4 // (see accompanying file LICENSE_1_0.txt or a copy at
5 // http://www.boost.org/LICENSE_1_0.txt)
6 // Home at http://www.boost.org/libs/local_function
7 
8 #include <boost/config.hpp>
9 #ifdef BOOST_NO_CXX11_VARIADIC_MACROS
10 #   error "variadic macros required"
11 #else
12 
13 #include <boost/local_function.hpp>
14 #include <boost/typeof/typeof.hpp>
15 #include BOOST_TYPEOF_INCREMENT_REGISTRATION_GROUP()
16 #include <boost/detail/lightweight_test.hpp>
17 #include <algorithm>
18 #include <vector>
19 
20 struct calculator;
21 BOOST_TYPEOF_REGISTER_TYPE(calculator) // Register before `bind this_` below.
22 
23 //[factorial
24 struct calculator {
25     std::vector<int> results;
26 
factorialscalculator27     void factorials(const std::vector<int>& nums) {
28         int BOOST_LOCAL_FUNCTION(bind this_, int num,
29                 bool recursion, default false) {
30             int result = 0;
31 
32             if(num <= 0) result = 1;
33             else result = num * factorial(num - 1, true); // Recursive call.
34 
35             if(!recursion) this_->results.push_back(result);
36             return result;
37         } BOOST_LOCAL_FUNCTION_NAME(recursive factorial) // Recursive.
38 
39         std::for_each(nums.begin(), nums.end(), factorial);
40     }
41 };
42 //]
43 
main(void)44 int main(void) {
45     std::vector<int> v(3);
46     v[0] = 1; v[1] = 3; v[2] = 4;
47 
48     calculator calc;
49     calc.factorials(v);
50     BOOST_TEST(calc.results[0] == 1);
51     BOOST_TEST(calc.results[1] == 6);
52     BOOST_TEST(calc.results[2] == 24);
53     return boost::report_errors();
54 }
55 
56 #endif // VARIADIC_MACROS
57 
58