XmlBind: putting PugXML on steroïds !

// iobind library
//
// author: Jonathan de Halleux, 2003

#ifndef IOBIND_STRING_POLICY_HPP
#define IOBIND_STRING_POLICY_HPP

#include <sstream>
#include <boost/spirit.hpp>
#include <iobind/policy.hpp>

namespace iobind{
namespace detail{

	template<
		char const* FormatString
	>
	struct to_string_policy
	{
		typedef std::string return_type;
		typedef std::string string_type;
		typedef std::string const& string_param_type;

		template<typename T>
		return_type encode( T const& value_) const
		{
			return boost::io::str( boost::format( FormatString ) % value_ );
		};
	};

	template<typename T>
	struct from_string_policy
	{
		typedef boost::call_traits<T>::value_type value_type;
		typedef boost::call_traits<T>::value_type return_type;
		typedef boost::call_traits<std::string>::param_type param_type;

		return_type encode( param_type str_) const
		{
			std::istringstream input(str_.c_str());
			value_type rt;
			input>>rt;

			if (!input.fail())
				return rt;
			else
				return return_type();
		};
	};


}; // detail

template<
	char const* FormatString
> 
struct to_string : 
	detail::policy_cons< detail::to_string_policy<FormatString> , detail::identity_policy >
{
	typedef detail::to_string_policy<FormatString> to_string_policy_type;
	typedef detail::policy_cons< to_string_policy_type  , detail::identity_policy > policy_type;
	typedef to_string type;
	typedef to_string_policy_type::string_param_type string_param_type;
};

template<typename T>
struct from_string : 
	detail::policy_cons< detail::from_string_policy<T> , detail::identity_policy >
{
	typedef from_string type;
};

extern const char* to_string_default_format_string;

typedef to_string<to_string_default_format_string> to_string_p_type;
const to_string_p_type to_string_p = to_string_p_type();

typedef from_string<std::string> from_string_p_type;
const from_string_p_type from_string_p = from_string_p_type();

}; //iobind


#endif