UnspecifiableOf.h

//========================================================================================
// 
// $File$
// 
// Owner: Michael Burbidge
// 
// $Author$
// 
// $DateTime$
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// $Revision$
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// Copyright 1997-2010 Adobe Systems Incorporated. All rights reserved.
// 
// NOTICE: Adobe permits you to use, modify, and distribute this file in accordance 
// with the terms of the Adobe license agreement accompanying it. If you have received
// this file from a source other than Adobe, then your use, modification, or 
// distribution of it requires the prior written permission of Adobe.
// 
//========================================================================================

#ifndef __UnspecifiableOf_h__
#define __UnspecifiableOf_h__

//========================================================================================
// TEMPLATE UnspecifiableOf
//========================================================================================

struct Unspecified { };

template <class ValueType>
class UnspecifiableOf
{
public:
 UnspecifiableOf(const Unspecified& /*unspecified*/) : fSpecified(false) { }
 
 UnspecifiableOf(const ValueType& value) : fSpecified(true), fValue(value) { }
 
 UnspecifiableOf(const UnspecifiableOf& other) : fSpecified(other.fSpecified), fValue(other.fValue) { }

 UnspecifiableOf<ValueType>& operator=(const UnspecifiableOf<ValueType>& other)
 {
 if (this != &other)
 {
 fSpecified = other.fSpecified;
 fValue = other.fValue;
 }
 
 return *this;
 }
 
 bool IsSpecified() const { return fSpecified; }
 
 ValueType GetValue() const { ASSERT(IsSpecified()); return fValue; }
 
private:
 bool fSpecified;
 ValueType fValue;
};

// was: extern const Unspecified kUnspecified;

#ifdef WINDOWS
// pjm - figure out what is going on here
const Unspecified kUnspecified;
#else
const Unspecified kUnspecified = {};
#endif

#endif // __UnspecifiableOf_h__