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41 lines
1.2 KiB
C++
41 lines
1.2 KiB
C++
/*
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@copyright Louis Dionne 2014
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Distributed under the Boost Software License, Version 1.0.
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(See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt)
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*/
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#include <boost/hana/adapted/std_integral_constant.hpp>
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#include <boost/hana/detail/constexpr.hpp>
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#include <boost/hana/detail/static_assert.hpp>
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#include <boost/hana/integral.hpp>
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#include <boost/hana/list.hpp>
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#include <boost/hana/logical.hpp>
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#include <boost/hana/type.hpp>
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#include <cassert>
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#include <sstream>
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#include <string>
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using namespace boost::hana;
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int main() {
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//! [fusion]
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auto to_string = [](auto x) { return (std::ostringstream{} << x).str(); };
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auto show = [=](auto x, auto y) {
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return "(" + to_string(x) + " + " + to_string(y) + ")";
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};
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assert(foldl(show, "1", list(2, "3", '4')) == "(((1 + 2) + 3) + 4)");
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//! [fusion]
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//! [mpl]
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BOOST_HANA_CONSTEXPR_LAMBDA auto types = list_t<long, float, short, double, float, long, long double>;
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BOOST_HANA_CONSTEXPR_LAMBDA auto count_if_float = [](auto c, auto t) {
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return if_(trait<std::is_floating_point>(t), c + int_<1>, c);
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};
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BOOST_HANA_STATIC_ASSERT(foldl(count_if_float, int_<0>, types) == int_<4>);
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//! [mpl]
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}
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