hana/example/cppcon_2014/matrix/monoid.hpp
2017-01-07 14:14:18 -08:00

38 lines
1.2 KiB
C++

// Copyright Louis Dionne 2013-2017
// Distributed under the Boost Software License, Version 1.0.
// (See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt)
#ifndef BOOST_HANA_EXAMPLE_CPPCON_2014_MATRIX_MONOID_HPP
#define BOOST_HANA_EXAMPLE_CPPCON_2014_MATRIX_MONOID_HPP
#include "matrix.hpp"
#include <boost/hana/integral_constant.hpp>
#include <boost/hana/concept/sequence.hpp>
#include <boost/hana/concept/monoid.hpp>
#include <boost/hana/range.hpp>
namespace boost { namespace hana {
template <unsigned R, unsigned C>
struct plus_impl<cppcon::Matrix<R, C>, cppcon::Matrix<R, C>> {
template <typename M1, typename M2>
static constexpr decltype(auto) apply(M1&& m1, M2&& m2) {
return element_wise(plus)(
std::forward<M1>(m1),
std::forward<M2>(m2)
);
}
};
template <unsigned R, unsigned C>
struct zero_impl<cppcon::Matrix<R, C>> {
static constexpr decltype(auto) apply() {
auto zeros = replicate(int_<0>, int_<C>);
return unpack(replicate(zeros, int_<R>), cppcon::matrix);
}
};
}}
#endif // !BOOST_HANA_EXAMPLE_CPPCON_2014_MATRIX_MONOID_HPP