property.h

#ifndef __SEAL_PROPERTY_H__
#define __SEAL_PROPERTY_H__

#ifndef NULL
#define NULL 0
#endif 

namespace seal
{

template <typename DataType, typename ParentType>
class Property
{

public:

    Property(ParentType *parentPtr, void (ParentType::*fptr)(DataType))
        : _parentPtr(parentPtr), _fptr(fptr)
    {}

    inline Property<DataType, ParentType>& operator=(const DataType &val)
    {
        if (val == _val)
            return *this;
        
        _val = val;

        if (_parentPtr != NULL)
            (_parentPtr->*_fptr)(val);

        return *this;
    }

    inline operator DataType() { return _val; }

private:
    DataType _val;
    void (ParentType::*_fptr)(DataType);
    ParentType *_parentPtr;

    Property(void) {} // Is declared private to force the user to use the proper 
                      // constructor.
};

} // End of namespace seal.

#endif // __SEAL_PROPERTY_H__

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