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98 lines
2.6 KiB
C++
98 lines
2.6 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/detail/assert.hpp>
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#include <boost/hana/detail/constexpr.hpp>
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#include <boost/hana/foreign.hpp>
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#include <boost/hana/integral.hpp>
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#include <boost/hana/range.hpp>
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#include <boost/hana/tuple.hpp>
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#include <sstream>
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using namespace boost::hana;
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int main() {
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//! [head]
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BOOST_HANA_CONSTEXPR_ASSERT(head(tuple(1, '2', 3.3, nullptr)) == 1);
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//! [head]
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//! [at]
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BOOST_HANA_CONSTEXPR_ASSERT(at(int_<0>, tuple(0, '1', 2.0)) == 0);
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BOOST_HANA_CONSTEXPR_ASSERT(at(int_<1>, tuple(0, '1', 2.0)) == '1');
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BOOST_HANA_CONSTEXPR_ASSERT(at(int_<2>, tuple(0, '1', 2.0)) == 2.0);
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//! [at]
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//! [drop]
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BOOST_HANA_CONSTEXPR_LAMBDA auto xs = tuple(0, '1', 2.0);
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BOOST_HANA_CONSTEXPR_ASSERT(drop(int_<0>, xs) == xs);
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BOOST_HANA_CONSTEXPR_ASSERT(drop(int_<1>, xs) == tuple('1', 2.0));
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BOOST_HANA_CONSTEXPR_ASSERT(drop(int_<2>, xs) == tuple(2.0));
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BOOST_HANA_CONSTANT_ASSERT(drop(int_<3>, xs) == tuple());
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BOOST_HANA_CONSTANT_ASSERT(drop(int_<4>, xs) == tuple());
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//! [drop]
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{
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//! [drop_until]
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using namespace literals;
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BOOST_HANA_CONSTEXPR_LAMBDA auto positive = [](auto x) {
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return x > int_<0>;
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};
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BOOST_HANA_CONSTANT_ASSERT(
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drop_until(positive, range(int_<-3>, int_<6>)) == range(int_<1>, int_<6>)
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);
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BOOST_HANA_CONSTANT_ASSERT(
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drop_until(positive, tuple(1_c, -2_c, 4_c, 5_c)) == tuple(1_c, -2_c, 4_c, 5_c)
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);
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//! [drop_until]
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}
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{
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//! [drop_while]
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using namespace literals;
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BOOST_HANA_CONSTEXPR_LAMBDA auto negative = [](auto x) {
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return x < int_<0>;
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};
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BOOST_HANA_CONSTANT_ASSERT(
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drop_while(negative, range(int_<-3>, int_<6>)) == range(int_<0>, int_<6>)
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);
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BOOST_HANA_CONSTANT_ASSERT(
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drop_while(negative, tuple(1_c, -2_c, 4_c, 5_c)) == tuple(1_c, -2_c, 4_c, 5_c)
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);
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//! [drop_while]
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}
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{
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//! [for_each]
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std::stringstream ss;
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for_each(tuple(0, '1', "234", 5.5), [&](auto x) {
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ss << x << ' ';
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});
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BOOST_HANA_RUNTIME_ASSERT(ss.str() == "0 1 234 5.5 ");
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//! [for_each]
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}
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//! [is_empty]
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BOOST_HANA_CONSTANT_ASSERT(!is_empty(tuple(1, '2')));
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BOOST_HANA_CONSTANT_ASSERT( is_empty(tuple()));
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//! [is_empty]
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//! [last]
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BOOST_HANA_CONSTEXPR_ASSERT(last(tuple(1, '2', 3.3, nullptr)) == nullptr);
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//! [last]
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//! [tail]
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BOOST_HANA_CONSTEXPR_ASSERT(
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tail(tuple(1, '2', 3.3, nullptr)) == tuple('2', 3.3, nullptr)
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);
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//! [tail]
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}
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