Conversions from T to std::string and from std::string to T

convert.hpp

#ifndef __CONVERT_HPP__
#define __CONVERT_HPP__

#include <iostream>
#include <sstream>
#include <string>
#include <stdexcept>

/**
 * \brief Conversion error exception
 */
class BadConversion : public std::runtime_error {
public:
	/**
	 * \brief Constructor
	 *
	 * \param s Message
	 */
	BadConversion(std::string const &s): std::runtime_error(s) {}
};

/**
 * \brief Convert x to an \c std::string
 *
 * \tparam T Type to convert
 * \param x Object to convert
 *
 * \return x converted to an \c std::string
 */
template<typename T>
inline std::string stringify(T const &x) {
	std::ostringstream o;
	if (!(o << x))
		throw BadConversion(std::string("stringify(") + typeid(x).name() + ")");
	return o.str();
}

/**
 * \brief Convert a \c std::string to type T
 *
 * \tparam T Type to convert
 * \param s Source string
 * \param x Object to convert into
 * \param failIfLeftoverChars If \c true, the conversion fails if the full string is not used
 */
template<typename T>
inline void convert(std::string const &s, T &x, bool failIfLeftoverChars = true) {
	std::istringstream i(s);
	char c;
	if (!(i >> x) || (failIfLeftoverChars && i.get(c)))
		throw BadConversion(s);
}

/**
 * \brief Convert a \c std::string to type T
 *
 * \tparam T Type to convert
 * \param s Source string
 * \param failIfLeftoverChars If \c true, the conversion fails if the full string is not used
 *
 * \return Converted object
 */
template<typename T>
inline T convert(std::string const &s, bool failIfLeftoverChars = true) {
	T x;
	convert(s, x, failIfLeftoverChars);
	return x;
}

#endif // __CONVERT_HPP__