libs/local_function/test/factorial.cpp
// 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/config.hpp>
#ifdef BOOST_NO_CXX11_VARIADIC_MACROS
# error "variadic macros required"
#else
#include <boost/local_function.hpp>
#include <boost/typeof/typeof.hpp>
#include BOOST_TYPEOF_INCREMENT_REGISTRATION_GROUP()
#include <boost/detail/lightweight_test.hpp>
#include <algorithm>
#include <vector>
struct calculator;
BOOST_TYPEOF_REGISTER_TYPE(calculator) // Register before `bind this_` below.
//[factorial
struct calculator {
std::vector<int> results;
void factorials(const std::vector<int>& nums) {
int BOOST_LOCAL_FUNCTION(bind this_, int num,
bool recursion, default false) {
int result = 0;
if(num <= 0) result = 1;
else result = num * factorial(num - 1, true); // Recursive call.
if(!recursion) this_->results.push_back(result);
return result;
} BOOST_LOCAL_FUNCTION_NAME(recursive factorial) // Recursive.
std::for_each(nums.begin(), nums.end(), factorial);
}
};
//]
int main(void) {
std::vector<int> v(3);
v[0] = 1; v[1] = 3; v[2] = 4;
calculator calc;
calc.factorials(v);
BOOST_TEST(calc.results[0] == 1);
BOOST_TEST(calc.results[1] == 6);
BOOST_TEST(calc.results[2] == 24);
return boost::report_errors();
}
#endif // VARIADIC_MACROS