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hana/example/list.cpp
2015-02-04 12:35:42 -05:00

440 lines
8.5 KiB
C++

/*
@copyright Louis Dionne 2014
Distributed under the Boost Software License, Version 1.0.
(See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt)
*/
#include <boost/hana/assert.hpp>
#include <boost/hana/detail/constexpr.hpp>
#include <boost/hana/ext/std/integral_constant.hpp>
#include <boost/hana/functional.hpp>
#include <boost/hana/integral_constant.hpp>
#include <boost/hana/maybe.hpp>
#include <boost/hana/pair.hpp>
#include <boost/hana/tuple.hpp>
#include <boost/hana/type.hpp>
#include <type_traits>
#include <sstream>
#include <string>
using namespace boost::hana;
int main() {
{
//! [cons]
BOOST_HANA_CONSTEXPR_CHECK(cons(1, tuple()) == tuple(1));
BOOST_HANA_CONSTEXPR_CHECK(cons(1, tuple('2', 3.3)) == tuple(1, '2', 3.3));
BOOST_HANA_CONSTEXPR_CHECK(cons(1, cons('2', cons(3.3, tuple()))) == tuple(1, '2', 3.3));
//! [cons]
}{
//! [filter]
BOOST_HANA_CONSTEXPR_CHECK(
filter(tuple(1, 2.0, 3, 4.0), trait_<std::is_integral>)
==
tuple(1, 3)
);
//! [filter]
}{
//! [make]
BOOST_HANA_CONSTANT_CHECK(make<Tuple>() == tuple());
BOOST_HANA_CONSTEXPR_CHECK(make<Tuple>(1, '2', 3.3) == tuple(1, '2', 3.3));
//! [make]
}{
//! [init]
using namespace literals;
BOOST_HANA_CONSTANT_CHECK(init(tuple(1)) == tuple());
BOOST_HANA_CONSTEXPR_CHECK(init(tuple(1, '2', 3.3, 4_c)) == tuple(1, '2', 3.3));
//! [init]
}{
//! [intersperse]
BOOST_HANA_CONSTEXPR_CHECK(intersperse(tuple(1, '2', 3.3), 'x') == tuple(1, 'x', '2', 'x', 3.3));
BOOST_HANA_CONSTANT_CHECK(intersperse(tuple(), 'x') == tuple());
//! [intersperse]
}{
//! [remove_at]
BOOST_HANA_CONSTEXPR_CHECK(
remove_at(int_<2>, tuple(0, '1', 2.2, 3u)) == tuple(0, '1', 3u)
);
//! [remove_at]
}{
//! [remove_at_c]
BOOST_HANA_CONSTEXPR_CHECK(
remove_at_c<2>(tuple(0, '1', 2.2, 3u)) == tuple(0, '1', 3u)
);
//! [remove_at_c]
}{
//! [reverse]
BOOST_HANA_CONSTEXPR_CHECK(reverse(tuple(1, '2', 3.3)) == tuple(3.3, '2', 1));
//! [reverse]
}{
//! [concat]
using namespace literals;
BOOST_HANA_CONSTEXPR_CHECK(
concat(tuple(1, '2'), tuple(3.3, 4_c)) == tuple(1, '2', 3.3, 4_c)
);
//! [concat]
}{
//! [group_by]
BOOST_HANA_CONSTEXPR_CHECK(
group_by(equal ^on^ decltype_,
tuple(1, 2, 3, 'x', 'y', 4.4, 5.5)
)
== tuple(
tuple(1, 2, 3),
tuple('x', 'y'),
tuple(4.4, 5.5)
)
);
//! [group_by]
}{
//! [group]
BOOST_HANA_CONSTANT_CHECK(
group(tuple(int_<1>, long_<1>, type<int>, char_<'x'>, char_<'x'>))
==
tuple(
tuple(int_<1>, long_<1>),
tuple(type<int>),
tuple(char_<'x'>, char_<'x'>)
)
);
//! [group]
}{
//! [zip]
BOOST_HANA_CONSTEXPR_CHECK(
zip(tuple(1, 'a'), tuple(2, 3.3))
==
tuple(tuple(1, 2), tuple('a', 3.3))
);
BOOST_HANA_CONSTEXPR_CHECK(
zip(tuple(1, 'a'), tuple(2, 3.3), tuple(3, 'c', "ignored"))
==
tuple(tuple(1, 2, 3), tuple('a', 3.3, 'c'))
);
//! [zip]
}{
//! [zip_with]
BOOST_HANA_CONSTEXPR_CHECK(
zip_with(_ * _, tuple(1, 2, 3, 4), tuple(5, 6, 7, 8, "ignored"))
==
tuple(5, 12, 21, 32)
);
//! [zip_with]
}{
//! [unzip]
BOOST_HANA_CONSTEXPR_CHECK(
unzip(tuple(tuple(1, '2', 3.3), tuple('4', 5.5, 6)))
==
tuple(tuple(1, '4'), tuple('2', 5.5), tuple(3.3, 6))
);
BOOST_HANA_CONSTEXPR_CHECK(
unzip(tuple(tuple(1, '2', 3.3), tuple('4', 5.5, 6, "ignored")))
==
tuple(tuple(1, '4'), tuple('2', 5.5), tuple(3.3, 6))
);
//! [unzip]
}{
//! [take_while]
using namespace literals;
BOOST_HANA_CONSTANT_CHECK(
take_while(tuple_c<int, 0, 1, 2, 3>, _ < 2_c)
==
tuple_c<int, 0, 1>
);
//! [take_while]
}{
//! [take_until]
using namespace literals;
BOOST_HANA_CONSTANT_CHECK(
take_until(tuple_c<int, 3, 2, 1, 0>, _ < 2_c)
==
tuple_c<int, 3, 2>
);
//! [take_until]
}{
//! [take]
using namespace literals;
BOOST_HANA_CONSTANT_CHECK(take(0_c, tuple(1, '2', 3.3)) == tuple());
BOOST_HANA_CONSTEXPR_CHECK(take(1_c, tuple(1, '2', 3.3)) == tuple(1));
BOOST_HANA_CONSTEXPR_CHECK(take(2_c, tuple(1, '2', 3.3)) == tuple(1, '2'));
BOOST_HANA_CONSTEXPR_CHECK(take(3_c, tuple(1, '2', 3.3)) == tuple(1, '2', 3.3));
BOOST_HANA_CONSTEXPR_CHECK(take(4_c, tuple(1, '2', 3.3)) == tuple(1, '2', 3.3));
//! [take]
}{
//! [take_c]
BOOST_HANA_CONSTEXPR_CHECK(take_c<2>(tuple(1, '2', 3.3)) == tuple(1, '2'));
//! [take_c]
}{
//! [snoc]
BOOST_HANA_CONSTEXPR_CHECK(snoc(tuple(), 1) == tuple(1));
BOOST_HANA_CONSTEXPR_CHECK(snoc(tuple(1, '2'), 3.3) == tuple(1, '2', 3.3));
BOOST_HANA_CONSTEXPR_CHECK(snoc(snoc(snoc(tuple(), 1), '2'), 3.3) == tuple(1, '2', 3.3));
//! [snoc]
}{
//! [repeat]
BOOST_HANA_CONSTEXPR_CHECK(repeat<Tuple>(int_<2>, 'x') == tuple('x', 'x'));
//! [repeat]
}{
//! [span]
BOOST_HANA_CONSTEXPR_LAMBDA auto xs = tuple(int_<1>, int_<2>, int_<3>, int_<4>);
BOOST_HANA_CONSTANT_CHECK(
span(xs, _ < int_<3>)
==
pair(tuple(int_<1>, int_<2>), tuple(int_<3>, int_<4>))
);
BOOST_HANA_CONSTANT_CHECK(
span(xs, _ < int_<0>)
==
pair(tuple(), xs)
);
BOOST_HANA_CONSTANT_CHECK(
span(xs, _ < int_<5>)
==
pair(xs, tuple())
);
//! [span]
}{
//! [sort]
using namespace literals;
BOOST_HANA_CONSTANT_CHECK(
sort(tuple(1_c, -2_c, 3_c, 0_c)) == tuple(-2_c, 0_c, 1_c, 3_c)
);
//! [sort]
}{
//! [sort_by]
using namespace literals;
BOOST_HANA_CONSTANT_CHECK(
sort_by(_>_, tuple(1_c, -2_c, 3_c, 0_c))
==
tuple(3_c, 1_c, 0_c, -2_c)
);
//! [sort_by]
}{
//! [nil]
BOOST_HANA_CONSTANT_CHECK(nil<Tuple>() == tuple());
//! [nil]
}{
//! [slice]
BOOST_HANA_CONSTEXPR_CHECK(
slice(tuple(1, '2', 3.3, type<float>), int_<1>, int_<3>)
==
tuple('2', 3.3)
);
//! [slice]
}{
//! [slice_c]
BOOST_HANA_CONSTEXPR_CHECK(
slice_c<1, 3>(tuple(1, '2', 3.3, type<float>))
==
tuple('2', 3.3)
);
//! [slice_c]
}{
//! [permutations]
BOOST_HANA_CONSTEXPR_LAMBDA auto is_permutation_of = curry<2>([](auto xs, auto perm) {
return elem(permutations(xs), perm);
});
BOOST_HANA_CONSTEXPR_CHECK(
all(
tuple(
tuple('1', 2, 3.0),
tuple('1', 3.0, 2),
tuple(2, '1', 3.0),
tuple(2, 3.0, '1'),
tuple(3.0, '1', 2),
tuple(3.0, 2, '1')
),
is_permutation_of(tuple('1', 2, 3.0))
)
);
//! [permutations]
}{
//! [unfoldl]
BOOST_HANA_CONSTEXPR_LAMBDA auto f = [](auto x) {
return if_(x == int_<0>, nothing, just(pair(x - int_<1>, x)));
};
BOOST_HANA_CONSTANT_CHECK(
unfoldl<IntegerList>(f, int_<10>)
==
tuple_c<int, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10>
);
//! [unfoldl]
}{
//! [unfoldr]
BOOST_HANA_CONSTEXPR_LAMBDA auto f = [](auto x) {
return if_(x == int_<0>, nothing, just(pair(x, x - int_<1>)));
};
BOOST_HANA_CONSTANT_CHECK(
unfoldr<IntegerList>(f, int_<10>)
==
tuple_c<int, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1>
);
//! [unfoldr]
}{
//! [scanl]
auto to_string = [](auto x) {
return static_cast<std::ostringstream const&>(std::ostringstream{} << x).str();
};
auto show = [=](auto x, auto y) {
return "(" + to_string(x) + " + " + to_string(y) + ")";
};
BOOST_HANA_RUNTIME_CHECK(scanl(tuple(2, "3", '4'), 1, show) == tuple(
1,
"(1 + 2)",
"((1 + 2) + 3)",
"(((1 + 2) + 3) + 4)"
));
//! [scanl]
}{
//! [scanl1]
auto to_string = [](auto x) {
return static_cast<std::ostringstream const&>(std::ostringstream{} << x).str();
};
auto show = [=](auto x, auto y) {
return "(" + to_string(x) + " + " + to_string(y) + ")";
};
BOOST_HANA_RUNTIME_CHECK(scanl1(tuple(1, "2", '3'), show) == tuple(
1,
"(1 + 2)",
"((1 + 2) + 3)"
));
//! [scanl1]
}{
//! [scanr]
auto to_string = [](auto x) {
return static_cast<std::ostringstream const&>(std::ostringstream{} << x).str();
};
auto show = [=](auto x, auto y) {
return "(" + to_string(x) + " + " + to_string(y) + ")";
};
BOOST_HANA_RUNTIME_CHECK(scanr(tuple(1, "2", '3'), 4, show) == tuple(
"(1 + (2 + (3 + 4)))",
"(2 + (3 + 4))",
"(3 + 4)",
4
));
//! [scanr]
}{
//! [scanr1]
auto to_string = [](auto x) {
return static_cast<std::ostringstream const&>(std::ostringstream{} << x).str();
};
auto show = [=](auto x, auto y) {
return "(" + to_string(x) + " + " + to_string(y) + ")";
};
BOOST_HANA_RUNTIME_CHECK(scanr1(tuple(1, "2", '3'), show) == tuple(
"(1 + (2 + 3))",
"(2 + 3)",
'3'
));
//! [scanr1]
}{
//! [partition]
BOOST_HANA_CONSTANT_CHECK(
partition(tuple_c<int, 1, 2, 3, 4, 5, 6, 7>, [](auto x) {
return x % int_<2> != int_<0>;
})
==
pair(
tuple_c<int, 1, 3, 5, 7>,
tuple_c<int, 2, 4, 6>
)
);
BOOST_HANA_CONSTANT_CHECK(
partition(tuple_t<void, int, float, char, double>, trait<std::is_floating_point>)
==
pair(
tuple_t<float, double>,
tuple_t<void, int, char>
)
);
//! [partition]
}
}