boost/test/data/monomorphic/join.hpp
// (C) Copyright Gennadiy Rozental 2001.
// Distributed under the Boost Software License, Version 1.0.
// (See accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
// See http://www.boost.org/libs/test for the library home page.
//
//! @file
//! Defines dataset join operation
// ***************************************************************************
#ifndef BOOST_TEST_DATA_MONOMORPHIC_JOIN_HPP_112711GER
#define BOOST_TEST_DATA_MONOMORPHIC_JOIN_HPP_112711GER
// Boost.Test
#include <boost/test/data/config.hpp>
#include <boost/test/data/monomorphic/fwd.hpp>
#include <boost/core/enable_if.hpp>
#include <boost/mpl/identity.hpp>
#include <boost/test/detail/suppress_warnings.hpp>
//____________________________________________________________________________//
namespace boost {
namespace unit_test {
namespace data {
namespace monomorphic {
// ************************************************************************** //
// ************** join ************** //
// ************************************************************************** //
//! Defines a new dataset from the concatenation of two datasets
//!
//! The size of the resulting dataset is the sum of the two underlying datasets. The arity of the datasets
//! should match.
template<typename DataSet1, typename DataSet2>
class join {
typedef typename boost::decay<DataSet1>::type dataset1_decay;
typedef typename boost::decay<DataSet2>::type dataset2_decay;
typedef typename dataset1_decay::iterator dataset1_iter;
typedef typename dataset2_decay::iterator dataset2_iter;
using iter1_ret = decltype(*std::declval<DataSet1>().begin());
using iter2_ret = decltype(*std::declval<DataSet2>().begin());
public:
enum { arity = dataset1_decay::arity };
using sample_t = typename std::conditional<
std::is_reference<iter1_ret>::value && std::is_reference<iter2_ret>::value && std::is_same<iter1_ret, iter2_ret>::value,
iter1_ret,
typename std::remove_reference<iter1_ret>::type
>::type
;
struct iterator {
// Constructor
explicit iterator( dataset1_iter&& it1, dataset2_iter&& it2, data::size_t first_size )
: m_it1( std::move( it1 ) )
, m_it2( std::move( it2 ) )
, m_first_size( first_size )
{}
// forward iterator interface
// The returned sample should be by value, as the operator* may return a temporary object
sample_t operator*() const { return m_first_size > 0 ? *m_it1 : *m_it2; }
void operator++() { if( m_first_size > 0 ) { --m_first_size; ++m_it1; } else ++m_it2; }
private:
// Data members
dataset1_iter m_it1;
dataset2_iter m_it2;
data::size_t m_first_size;
};
//! Constructor
join( DataSet1&& ds1, DataSet2&& ds2 )
: m_ds1( std::forward<DataSet1>( ds1 ) )
, m_ds2( std::forward<DataSet2>( ds2 ) )
{}
//! Move constructor
join( join&& j )
: m_ds1( std::forward<DataSet1>( j.m_ds1 ) )
, m_ds2( std::forward<DataSet2>( j.m_ds2 ) )
{}
//! dataset interface
data::size_t size() const { return m_ds1.size() + m_ds2.size(); }
iterator begin() const { return iterator( m_ds1.begin(), m_ds2.begin(), m_ds1.size() ); }
private:
// Data members
DataSet1 m_ds1;
DataSet2 m_ds2;
};
//____________________________________________________________________________//
// A joined dataset is a dataset.
template<typename DataSet1, typename DataSet2>
struct is_dataset<join<DataSet1,DataSet2>> : mpl::true_ {};
//____________________________________________________________________________//
namespace result_of {
//! Result type of the join operation on datasets.
template<typename DataSet1Gen, typename DataSet2Gen>
struct join {
typedef monomorphic::join<typename DataSet1Gen::type,typename DataSet2Gen::type> type;
};
} // namespace result_of
//____________________________________________________________________________//
template<typename DataSet1, typename DataSet2>
inline typename boost::lazy_enable_if_c<is_dataset<DataSet1>::value && is_dataset<DataSet2>::value,
result_of::join<mpl::identity<DataSet1>,mpl::identity<DataSet2>>
>::type
operator+( DataSet1&& ds1, DataSet2&& ds2 )
{
return join<DataSet1,DataSet2>( std::forward<DataSet1>( ds1 ), std::forward<DataSet2>( ds2 ) );
}
//____________________________________________________________________________//
template<typename DataSet1, typename DataSet2>
inline typename boost::lazy_enable_if_c<is_dataset<DataSet1>::value && !is_dataset<DataSet2>::value,
result_of::join<mpl::identity<DataSet1>,data::result_of::make<DataSet2>>
>::type
operator+( DataSet1&& ds1, DataSet2&& ds2 )
{
return std::forward<DataSet1>( ds1 ) + data::make( std::forward<DataSet2>( ds2 ) );
}
//____________________________________________________________________________//
template<typename DataSet1, typename DataSet2>
inline typename boost::lazy_enable_if_c<!is_dataset<DataSet1>::value && is_dataset<DataSet2>::value,
result_of::join<data::result_of::make<DataSet1>,mpl::identity<DataSet2>>
>::type
operator+( DataSet1&& ds1, DataSet2&& ds2 )
{
return data::make( std::forward<DataSet1>(ds1) ) + std::forward<DataSet2>( ds2 );
}
} // namespace monomorphic
} // namespace data
} // namespace unit_test
} // namespace boost
#include <boost/test/detail/enable_warnings.hpp>
#endif // BOOST_TEST_DATA_MONOMORPHIC_JOIN_HPP_112711GER