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// DR 339

//

// Test of the use of the ternary operator with SFINAE

// Boilerplate helpers

typedef char yes_type;

struct no_type { char data[2]; };

template T create_a();

template struct type { };

template struct enable_if { typedef T type; };

template struct enable_if { };

#define JOIN( X, Y ) DO_JOIN( X, Y )

#define DO_JOIN( X, Y ) DO_JOIN2(X,Y)

#define DO_JOIN2( X, Y ) X##Y

template

typename enable_if<

           (sizeof((create_a()? create_a() : create_a()), 0) > 0),

           yes_type>::type

  check_ternary(int);

template no_type check_ternary(...);

template

struct has_ternary

{

  static const bool value =

    (sizeof(check_ternary(0)) == sizeof(yes_type));

};

#ifdef __GXX_EXPERIMENTAL_CXX0X__

#  define STATIC_ASSERT(Expr) static_assert(Expr, #Expr)

#else

#  define STATIC_ASSERT(Expr) int JOIN(a,__LINE__)[Expr? 1 : -1]

#endif

struct X { };

struct Y { operator bool(); };

STATIC_ASSERT((has_ternary::value));

STATIC_ASSERT((has_ternary::value));

STATIC_ASSERT((!has_ternary::value));

STATIC_ASSERT((!has_ternary::value));

STATIC_ASSERT((has_ternary::value));