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127 lines
3.0 KiB
C++
127 lines
3.0 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/assert.hpp>
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#include <boost/hana/detail/constexpr.hpp>
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#include <boost/hana/ext/std/integral_constant.hpp>
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#include <boost/hana/integral_constant.hpp>
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#include <boost/hana/maybe.hpp>
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#include <boost/hana/range.hpp>
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#include <boost/hana/tuple.hpp>
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#include <boost/hana/type.hpp>
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#include <sstream>
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#include <type_traits>
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using namespace boost::hana;
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int main() {
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{
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//! [head]
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BOOST_HANA_CONSTEXPR_CHECK(head(make<Tuple>(1, '2', 3.3, nullptr)) == 1);
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//! [head]
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}{
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//! [at]
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BOOST_HANA_CONSTEXPR_CHECK(at(int_<0>, make<Tuple>(0, '1', 2.0)) == 0);
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BOOST_HANA_CONSTEXPR_CHECK(at(int_<1>, make<Tuple>(0, '1', 2.0)) == '1');
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BOOST_HANA_CONSTEXPR_CHECK(at(int_<2>, make<Tuple>(0, '1', 2.0)) == 2.0);
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//! [at]
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}{
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//! [at_c]
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BOOST_HANA_CONSTEXPR_CHECK(at_c<0>(make<Tuple>(0, '1', 2.0)) == 0);
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BOOST_HANA_CONSTEXPR_CHECK(at_c<1>(make<Tuple>(0, '1', 2.0)) == '1');
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BOOST_HANA_CONSTEXPR_CHECK(at_c<2>(make<Tuple>(0, '1', 2.0)) == 2.0);
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//! [at_c]
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}{
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//! [drop]
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constexpr auto xs = make<Tuple>(0, '1', 2.0);
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BOOST_HANA_CONSTEXPR_CHECK(drop(int_<0>, xs) == xs);
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BOOST_HANA_CONSTEXPR_CHECK(drop(int_<1>, xs) == make<Tuple>('1', 2.0));
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BOOST_HANA_CONSTEXPR_CHECK(drop(int_<2>, xs) == make<Tuple>(2.0));
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BOOST_HANA_CONSTANT_CHECK(drop(int_<3>, xs) == make<Tuple>());
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BOOST_HANA_CONSTANT_CHECK(drop(int_<4>, xs) == make<Tuple>());
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//! [drop]
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}{
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//! [drop_c]
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BOOST_HANA_CONSTEXPR_CHECK(drop_c<2>(make<Tuple>(0, '1', 2.0)) == make<Tuple>(2.0));
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//! [drop_c]
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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_CHECK(
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drop_until(range(int_<-3>, int_<6>), positive) == range(int_<1>, int_<6>)
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);
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BOOST_HANA_CONSTANT_CHECK(
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drop_until(make<Tuple>(1_c, -2_c, 4_c, 5_c), positive) == make<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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//! [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_CHECK(
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drop_while(range(int_<-3>, int_<6>), negative) == range(int_<0>, int_<6>)
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);
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BOOST_HANA_CONSTANT_CHECK(
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drop_while(make<Tuple>(1_c, -2_c, 4_c, 5_c), negative) == make<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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//! [is_empty]
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BOOST_HANA_CONSTANT_CHECK(!is_empty(make<Tuple>(1, '2')));
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BOOST_HANA_CONSTANT_CHECK( is_empty(make<Tuple>()));
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//! [is_empty]
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}{
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//! [last]
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BOOST_HANA_CONSTEXPR_CHECK(last(make<Tuple>(1, '2', 3.3, nullptr)) == nullptr);
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//! [last]
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}{
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//! [tail]
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BOOST_HANA_CONSTEXPR_CHECK(
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tail(make<Tuple>(1, '2', 3.3, nullptr)) == make<Tuple>('2', 3.3, nullptr)
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);
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//! [tail]
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}{
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//! [find]
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BOOST_HANA_CONSTEXPR_CHECK(find(make<Tuple>(1.0, 2, '3'), trait_<std::is_integral>) == just(2));
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BOOST_HANA_CONSTANT_CHECK(find(make<Tuple>(1.0, 2, '3'), trait_<std::is_class>) == nothing);
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//! [find]
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}
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}
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