70 lines
2.8 KiB
C++
70 lines
2.8 KiB
C++
/***************************************************************************
|
|
* Copyright (C) 2008-2021 by Andrzej Rybczak *
|
|
* andrzej@rybczak.net *
|
|
* *
|
|
* This program is free software; you can redistribute it and/or modify *
|
|
* it under the terms of the GNU General Public License as published by *
|
|
* the Free Software Foundation; either version 2 of the License, or *
|
|
* (at your option) any later version. *
|
|
* *
|
|
* This program is distributed in the hope that it will be useful, *
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of *
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
|
|
* GNU General Public License for more details. *
|
|
* *
|
|
* You should have received a copy of the GNU General Public License *
|
|
* along with this program; if not, write to the *
|
|
* Free Software Foundation, Inc., *
|
|
* 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. *
|
|
***************************************************************************/
|
|
|
|
#ifndef NCMPCPP_HELPERS_SONG_ITERATOR_MAKER_H
|
|
#define NCMPCPP_HELPERS_SONG_ITERATOR_MAKER_H
|
|
|
|
#include <boost/iterator/transform_iterator.hpp>
|
|
#include "curses/menu.h"
|
|
#include "song_list.h"
|
|
|
|
template <typename SongT>
|
|
struct SongPropertiesExtractor
|
|
{
|
|
template <typename ItemT>
|
|
auto &operator()(ItemT &item) const
|
|
{
|
|
return m_cache.assign(&item.properties(), &item.value());
|
|
}
|
|
|
|
private:
|
|
mutable SongProperties m_cache;
|
|
};
|
|
|
|
template <typename IteratorT>
|
|
SongIterator makeSongIterator(IteratorT it)
|
|
{
|
|
typedef SongPropertiesExtractor<
|
|
typename IteratorT::value_type::Type
|
|
> Extractor;
|
|
static_assert(
|
|
std::is_convertible<
|
|
typename std::result_of<Extractor(typename IteratorT::reference)>::type,
|
|
SongProperties &
|
|
>::value, "invalid result type of SongPropertiesExtractor");
|
|
return SongIterator(boost::make_transform_iterator(it, Extractor{}));
|
|
}
|
|
|
|
template <typename ConstIteratorT>
|
|
ConstSongIterator makeConstSongIterator(ConstIteratorT it)
|
|
{
|
|
typedef SongPropertiesExtractor<
|
|
typename ConstIteratorT::value_type::Type
|
|
> Extractor;
|
|
static_assert(
|
|
std::is_convertible<
|
|
typename std::result_of<Extractor(typename ConstIteratorT::reference)>::type,
|
|
const SongProperties &
|
|
>::value, "invalid result type of SongPropertiesExtractor");
|
|
return ConstSongIterator(boost::make_transform_iterator(it, Extractor{}));
|
|
}
|
|
|
|
#endif // NCMPCPP_HELPERS_SONG_ITERATOR_MAKER_H
|