K2TypeTraits.h

//========================================================================================
// 
// $File$
// 
// Owner: Mat Marcus
// 
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// $DateTime$
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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 __K2TypeTraits__
#define __K2TypeTraits__

#include "MetaProgramming.h"

#define BOOST_HAS_THREADS 

#include <boost/shared_ptr.hpp>

// ===================================================================================
// PODTraits
// POD stands for Plain Old Data
// ===================================================================================

struct base_type { typedef base_type data_type;};
struct object_type{ typedef object_type data_type;};


template <class T>
class PODTraits { 
public:
 typedef typename K2Meta::IF<K2Meta::IS_PTR<T>::RET /*|| K2Meta::IS_ENUM<T>::RET*/, base_type, T>::RET::data_type data_type; 
};


#define DECLARE_BASE_TYPE(type) \
template <> \
class PODTraits<type > { \
public: \
 typedef base_type data_type; \
} \

#define DECLARE_OBJECT_TYPE(type) \
template <> \
class PODTraits<type > { \
public: \
 typedef object_type data_type; \
} 

 
// ===================================================================================
// Specializations for common base types
// ===================================================================================
DECLARE_BASE_TYPE(bool);
DECLARE_BASE_TYPE(char);
DECLARE_BASE_TYPE(short);
DECLARE_BASE_TYPE(int);
DECLARE_BASE_TYPE(long);
DECLARE_BASE_TYPE(unsigned char);
DECLARE_BASE_TYPE(unsigned short);
DECLARE_BASE_TYPE(unsigned int);
DECLARE_BASE_TYPE(unsigned long);
#if defined WINDOWS
DECLARE_BASE_TYPE(__int64);
DECLARE_BASE_TYPE(unsigned __int64);
#else
DECLARE_BASE_TYPE(long long);
DECLARE_BASE_TYPE(unsigned long long);
#endif
DECLARE_BASE_TYPE(float);
DECLARE_BASE_TYPE(double);
DECLARE_BASE_TYPE(long double);

DECLARE_BASE_TYPE(const void*); 

template <typename T> \
class PODTraits<boost::shared_ptr<T>> { \
public: \
 typedef object_type data_type; \
}; \

namespace K2Meta { 

// ----- IS_POD -----
 template <class T>
 struct IsPOD {
 enum {RET = false};
 };

 template <>
 struct IsPOD<base_type> {
 enum {RET = true};
 };

 template <class T>
 struct IS_POD {
 enum {RET = IsPOD<typename PODTraits<T>::data_type>::RET};
 };

// ----- IS_POD_PTR -----

#if HAS_PARTIAL_SPECIALIZATION
 template <typename T>
 struct IS_POD_PTR {
 enum { RET = false};
 };
 
 template <typename T>
 struct IS_POD_PTR<const T*> {
 enum { RET = K2Meta::IS_POD<T>::RET };
 };
 template <typename T>
 struct IS_POD_PTR<T*> {
 enum { RET = K2Meta::IS_POD<T>::RET };
 };


#else
 template class IF<1, int, char>; // for VC6.4

 template <class Q>
 typename IF<IS_POD<Q>::RET, int, char>::RET IsPODPtr(const Q*);
 
 char IsPODPtr(...);

 template <class Q>
 struct IS_POD_PTR { 
 static Q q;
 public:
 enum { RET = sizeof(IsPODPtr(q)) == sizeof(int) };
 };
#endif
} // namespace K2Meta

 
 template <typename T>
 struct CONVERSION_TO_THREADLOCALSTORAGE {
 static T CONVERT(T arg) {return arg;}
 };

#endif //__K2TypeTraits__