DataSourceGenerator.hpp

/***************************************************************************
  tag: Peter Soetens  Wed Jan 18 14:11:40 CET 2006  DataSourceGenerator.hpp

                        DataSourceGenerator.hpp -  description
                           -------------------
    begin                : Wed January 18 2006
    copyright            : (C) 2006 Peter Soetens
    email                : peter.soetens@mech.kuleuven.be

 ***************************************************************************
 *   This library is free software; you can redistribute it and/or         *
 *   modify it under the terms of the GNU General Public                   *
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 *   version 2 of the License.                                             *
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 *   software library without restriction.  Specifically, if other files   *
 *   instantiate templates or use macros or inline functions from this     *
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 *   resulting executable to be covered by the GNU General Public          *
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 *   Public License.                                                       *
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#ifndef ORO_EXECUTION_DATASOURCE_GENERATOR_HPP
#define ORO_EXECUTION_DATASOURCE_GENERATOR_HPP

#include "DataSources.hpp"
#include <boost/utility/enable_if.hpp>
#include <boost/ref.hpp>

namespace RTT
{
    namespace detail
    {
        template<class T, class Enable = void >
        struct DSWrap {
            DataSourceBase::shared_ptr operator()(T t) { return new ConstantDataSource<T>( t );}
        }; // normal type

        template<class T>
        struct DSWrap<T, typename boost::enable_if< boost::is_base_and_derived<DataSourceBase,T> >::type > {
            DataSourceBase::shared_ptr operator()(T t) { return t; }
        }; // datasource type

        template<class T>
        struct DSWrap<T, typename boost::enable_if< boost::is_reference<T> >::type > {
            DataSourceBase::shared_ptr operator()(T t) { return new ReferenceDataSource<T>( t ); }
        }; // datasource type

        template<class T>
        struct DSWrap<T, typename boost::enable_if< boost::is_reference_wrapper<T> >::type > {
            typedef typename boost::unwrap_reference<T>::type RT;
            DataSourceBase::shared_ptr operator()(T t) { return new ReferenceDataSource<RT>( t ); }
        }; // datasource type
    }

    using boost::ref;

    struct GenerateDataSource
    {
        template<class A1>
        std::vector<DataSourceBase::shared_ptr> operator()(A1 a1)
        {
            std::vector<DataSourceBase::shared_ptr> res;
            res.push_back( detail::DSWrap<A1>()(a1));
            return res;
        }

        template<class A1, class A2>
        std::vector<DataSourceBase::shared_ptr> operator()(A1 a1, A2 a2 )
        {
            std::vector<DataSourceBase::shared_ptr> res = operator()(a1);
            res.push_back( detail::DSWrap<A2>()(a2));
            return res;
        }

        template<class A1, class A2, class A3>
        std::vector<DataSourceBase::shared_ptr> operator()(A1 a1, A2 a2, A3 a3 )
        {
            std::vector<DataSourceBase::shared_ptr> res = operator()(a1,a2);
            res.push_back( detail::DSWrap<A3>()(a3));
            return res;
        }

        template<class A1, class A2, class A3, class A4>
        std::vector<DataSourceBase::shared_ptr> operator()(A1 a1, A2 a2, A3 a3, A4 a4 )
        {
            std::vector<DataSourceBase::shared_ptr> res = operator()(a1,a2,a3);
            res.push_back( detail::DSWrap<A4>()(a4));
            return res;
        }
    };
}

#endif