reader_variable.h

/*****************************************************************************
* Multiscale Universal Interface Code Coupling Library                       *
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* Copyright (C) 2019 Y. H. Tang, S. Kudo, X. Bian, Z. Li, G. E. Karniadakis  *
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* ** GNU General Public License, version 3 **                                *
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/**
 * @file reader_variable.h
 * @author Y. H. Tang
 * @date 11 March 2014
 * @brief Creates a structure to parse a message as variables and pass them
 * to a function as arguments.
 */

#ifndef READER_VARIABLE_H_
#define READER_VARIABLE_H_

#include <tuple>
#include <functional>
#include <utility>
#include "message.h"
#include "stream.h"
#include "stream_tuple.h"
#include "stream_string.h"

namespace mui
{

// parse message as variables and pass them to f as arguments of it
template<typename... Args>
struct reader_variables {
	typedef std::function<void(Args...)> function_type;
	typedef std::tuple<typename std::remove_reference<Args>::type...> tuple_type;

	reader_variables() = default;
	reader_variables( function_type f ) : f_(std::move(f)) {}
	void operator()( const message& msg ){
		// parse msg as tuple of variables
		auto stream = make_istream(msg.data());
		tuple_type t;
		stream >> t;
		// split tuple before applying
		apply(t, typename make_index_sequence<sizeof...(Args)>::type());
	}
private:
	template<std::size_t... indexes>
	void apply( tuple_type& t, index_sequence<indexes...> ){
		f_(std::get<indexes>(std::move(t))...);
	}
	function_type f_;
};

}


#endif /* READER_VARIABLE_H_ */