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Files
hana/example/iterable.cpp
Louis Dionne 26af39f3d9 Flip the arguments of several methods.
Flipped:
- traverse
- fmap, adjust, fill, replace
- drop_while, drop_until
- take_while, take_until
2014-08-29 10:24:19 -04:00

113 lines
3.1 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/detail/assert.hpp>
#include <boost/hana/detail/constexpr.hpp>
#include <boost/hana/foreign.hpp>
#include <boost/hana/integral.hpp>
#include <boost/hana/range.hpp>
#include <boost/hana/tuple.hpp>
#include <sstream>
using namespace boost::hana;
int main() {
{
//! [head]
BOOST_HANA_CONSTEXPR_ASSERT(head(tuple(1, '2', 3.3, nullptr)) == 1);
//! [head]
}
{
//! [at]
BOOST_HANA_CONSTEXPR_ASSERT(at(int_<0>, tuple(0, '1', 2.0)) == 0);
BOOST_HANA_CONSTEXPR_ASSERT(at(int_<1>, tuple(0, '1', 2.0)) == '1');
BOOST_HANA_CONSTEXPR_ASSERT(at(int_<2>, tuple(0, '1', 2.0)) == 2.0);
//! [at]
}
{
//! [at_c]
BOOST_HANA_CONSTEXPR_ASSERT(at_c<0>(tuple(0, '1', 2.0)) == 0);
BOOST_HANA_CONSTEXPR_ASSERT(at_c<1>(tuple(0, '1', 2.0)) == '1');
BOOST_HANA_CONSTEXPR_ASSERT(at_c<2>(tuple(0, '1', 2.0)) == 2.0);
//! [at_c]
}
{
//! [drop]
BOOST_HANA_CONSTEXPR_LAMBDA auto xs = tuple(0, '1', 2.0);
BOOST_HANA_CONSTEXPR_ASSERT(drop(int_<0>, xs) == xs);
BOOST_HANA_CONSTEXPR_ASSERT(drop(int_<1>, xs) == tuple('1', 2.0));
BOOST_HANA_CONSTEXPR_ASSERT(drop(int_<2>, xs) == tuple(2.0));
BOOST_HANA_CONSTANT_ASSERT(drop(int_<3>, xs) == tuple());
BOOST_HANA_CONSTANT_ASSERT(drop(int_<4>, xs) == tuple());
//! [drop]
}
{
//! [drop_c]
BOOST_HANA_CONSTEXPR_ASSERT(drop_c<2>(tuple(0, '1', 2.0)) == tuple(2.0));
//! [drop_c]
}
{
//! [drop_until]
using namespace literals;
BOOST_HANA_CONSTEXPR_LAMBDA auto positive = [](auto x) {
return x > int_<0>;
};
BOOST_HANA_CONSTANT_ASSERT(
drop_until(range(int_<-3>, int_<6>), positive) == range(int_<1>, int_<6>)
);
BOOST_HANA_CONSTANT_ASSERT(
drop_until(tuple(1_c, -2_c, 4_c, 5_c), positive) == tuple(1_c, -2_c, 4_c, 5_c)
);
//! [drop_until]
}
{
//! [drop_while]
using namespace literals;
BOOST_HANA_CONSTEXPR_LAMBDA auto negative = [](auto x) {
return x < int_<0>;
};
BOOST_HANA_CONSTANT_ASSERT(
drop_while(range(int_<-3>, int_<6>), negative) == range(int_<0>, int_<6>)
);
BOOST_HANA_CONSTANT_ASSERT(
drop_while(tuple(1_c, -2_c, 4_c, 5_c), negative) == tuple(1_c, -2_c, 4_c, 5_c)
);
//! [drop_while]
}
{
//! [is_empty]
BOOST_HANA_CONSTANT_ASSERT(!is_empty(tuple(1, '2')));
BOOST_HANA_CONSTANT_ASSERT( is_empty(tuple()));
//! [is_empty]
}
{
//! [last]
BOOST_HANA_CONSTEXPR_ASSERT(last(tuple(1, '2', 3.3, nullptr)) == nullptr);
//! [last]
}
{
//! [tail]
BOOST_HANA_CONSTEXPR_ASSERT(
tail(tuple(1, '2', 3.3, nullptr)) == tuple('2', 3.3, nullptr)
);
//! [tail]
}
}