Null.h

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/*
 * Null.h
 *
 *  Created on: 2012-8-23
 *      Author: fasiondog
 */

#ifndef NULL_H_
#define NULL_H_

#include <boost/limits.hpp>
#include <boost/type_traits.hpp>

namespace hku {

template <typename T>
class Null {
public:
    Null() {}
    operator T() const {
        return T();
    }
};

template <>
class Null<int> {
public:
    Null() {}
    operator int() {
        return (std::numeric_limits<int>::max)();
    }
};

template <>
class Null<unsigned int> {
public:
    Null() {}
    operator unsigned int() {
        return (std::numeric_limits<unsigned int>::max)();
    }
};

template <>
class Null<long long> {
public:
    Null() {}
    operator long long() {
        return (std::numeric_limits<long long>::max)();
    }
};

template <>
class Null<unsigned long long> {
public:
    Null() {}
    operator unsigned long long() {
        return (std::numeric_limits<unsigned long long>::max)();
    }
};

#if !defined(BOOST_MSVC)

template <>
class Null<size_t> {
public:
    Null() {}
    operator unsigned long long() {
        return (std::numeric_limits<size_t>::max)();
    }
};
#endif

template <>
class Null<double> {
public:
    Null() {}
    operator double() {
        return (std::numeric_limits<double>::max)();
    }
};

} /* namesapce hku */

#endif /* NULL_H_ */