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// Copyright (C) 2016-2018 T. Zachary Laine
//
// Distributed under 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)
//[ calc2a
#include <boost/yap/expression.hpp>
#include <iostream>
int main ()
{
using namespace boost::yap::literals;
auto expr_1 = 1_p + 2.0;
auto expr_1_fn = [expr_1](auto &&... args) {
return evaluate(expr_1, args...);
};
auto expr_2 = 1_p * 2_p;
auto expr_2_fn = [expr_2](auto &&... args) {
return evaluate(expr_2, args...);
};
auto expr_3 = (1_p - 2_p) / 2_p;
auto expr_3_fn = [expr_3](auto &&... args) {
return evaluate(expr_3, args...);
};
// Displays "5"
std::cout << expr_1_fn(3.0) << std::endl;
// Displays "6"
std::cout << expr_2_fn(3.0, 2.0) << std::endl;
// Displays "0.5"
std::cout << expr_3_fn(3.0, 2.0) << std::endl;
return 0;
}
//]
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