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#ifndef STXXL_META_TEMPLATE_PROGRAMMING
#define STXXL_META_TEMPLATE_PROGRAMMING
/***************************************************************************
* tmeta.h
* Template Metaprogramming Tools
* (from the Generative Programming book Krysztof Czarnecki, Ulrich Eisenecker)
* Thu May 29 11:43:44 2003
* Copyright 2003 Roman Dementiev
* dementiev@mpi-sb.mpg.de
****************************************************************************/
#include "../common/utils.h"
__STXXL_BEGIN_NAMESPACE
//! \brief IF template metaprogramming statement
//! If \c Flag is \c true then \c IF<>::result is of type Type1
//! otherwise of \c IF<>::result is of type Type2
template <bool Flag,class Type1, class Type2>
struct IF
{
typedef Type1 result;
};
template <class Type1, class Type2>
struct IF<false,Type1,Type2>
{
typedef Type2 result;
};
const int DEFAULT = ~(~0u >> 1); // initialize with the smallest int
struct NilCase {};
template <int tag_,class Type_,class Next_ = NilCase>
struct CASE
{
enum { tag = tag_ };
typedef Type_ Type;
typedef Next_ Next;
};
template <int tag,class Case>
class SWITCH
{
typedef typename Case::Next NextCase;
enum
{
caseTag = Case::tag,
found = (caseTag == tag || caseTag == DEFAULT)
};
public:
typedef typename IF<found,
typename Case::Type,
typename SWITCH<tag,NextCase>::result
>::result result;
};
template <int tag>
class SWITCH<tag,NilCase>
{
public:
typedef NilCase result;
};
__STXXL_END_NAMESPACE
#endif