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// DR 339
//
// Test of the use of various unary operators with SFINAE
// { dg-options "-fmessage-length=0 -pedantic-errors -Wno-long-long -ftrack-macro-expansion=0 " }
// Boilerplate helpers
typedef char yes_type;
struct no_type { char data[2]; };
template<typename T> T create_a();
template<typename T> struct type { };
template<bool, typename T = void> struct enable_if { typedef T type; };
template<typename T> struct enable_if<false, T> { };
#define JOIN( X, Y ) DO_JOIN( X, Y )
#define DO_JOIN( X, Y ) DO_JOIN2(X,Y)
#define DO_JOIN2( X, Y ) X##Y
#define DEFINE_PREFIX_UNARY_TRAIT(Name,Op) \
template<typename T> \
typename enable_if<(sizeof(Op create_a<T>(), 1) > 0), \
yes_type>::type \
JOIN(check_,Name)(int); \
\
template<typename T> \
no_type JOIN(check_,Name)(...); \
\
template<typename T> \
struct Name \
{ \
static const bool value = \
(sizeof(JOIN(check_,Name)<T&>(0)) == sizeof(yes_type)); \
}
#define DEFINE_POSTFIX_UNARY_TRAIT(Name,Op) \
template<typename T> \
typename enable_if<(sizeof(create_a<T>() Op, 1) > 0), \
yes_type>::type \
JOIN(check_,Name)(int); \
\
template<typename T> \
no_type JOIN(check_,Name)(...); \
\
template<typename T> \
struct Name \
{ \
static const bool value = \
(sizeof(JOIN(check_,Name)<T&>(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 W {
W operator+();
W operator-();
int operator*();
W operator~();
bool operator!();
W& operator++();
W& operator--();
W& operator++(int);
W& operator--(int);
};
struct X { };
X operator+(X);
X operator-(X);
int operator*(X);
X operator~(X);
bool operator!(X);
X& operator++(X&);
X& operator--(X&);
X& operator++(X&, int);
X& operator--(X&, int);
struct Y { };
struct Z {
private:
Z operator+();
Z operator-();
int operator*();
Z operator~();
bool operator!();
Z& operator++();
Z& operator--();
Z& operator++(int);
Z& operator--(int);
};
// has_unary_plus
DEFINE_PREFIX_UNARY_TRAIT(has_unary_plus, +);
STATIC_ASSERT((has_unary_plus<int>::value));
STATIC_ASSERT((!has_unary_plus<int X::*>::value));
STATIC_ASSERT((has_unary_plus<W>::value));
STATIC_ASSERT((has_unary_plus<X>::value));
STATIC_ASSERT((!has_unary_plus<Y>::value));
// is_negatable
DEFINE_PREFIX_UNARY_TRAIT(is_negatable, -);
STATIC_ASSERT((is_negatable<int>::value));
STATIC_ASSERT((!is_negatable<int X::*>::value));
STATIC_ASSERT((is_negatable<W>::value));
STATIC_ASSERT((is_negatable<X>::value));
STATIC_ASSERT((!is_negatable<Y>::value));
// is_dereferenceable
DEFINE_PREFIX_UNARY_TRAIT(is_dereferenceable, *);
STATIC_ASSERT((!is_dereferenceable<int>::value));
STATIC_ASSERT((is_dereferenceable<int*>::value));
STATIC_ASSERT((is_dereferenceable<W>::value));
STATIC_ASSERT((is_dereferenceable<X>::value));
STATIC_ASSERT((!is_dereferenceable<Y>::value));
// has_bitwise_not
DEFINE_PREFIX_UNARY_TRAIT(has_bitwise_not, ~);
STATIC_ASSERT((has_bitwise_not<int>::value));
STATIC_ASSERT((!has_bitwise_not<int*>::value));
STATIC_ASSERT((has_bitwise_not<W>::value));
STATIC_ASSERT((has_bitwise_not<X>::value));
STATIC_ASSERT((!has_bitwise_not<Y>::value));
// has_truth_not
DEFINE_PREFIX_UNARY_TRAIT(has_truth_not, !);
STATIC_ASSERT((has_truth_not<int>::value));
STATIC_ASSERT((has_truth_not<int*>::value));
STATIC_ASSERT((has_truth_not<W>::value));
STATIC_ASSERT((has_truth_not<X>::value));
STATIC_ASSERT((!has_truth_not<Y>::value));
// has_preincrement
DEFINE_PREFIX_UNARY_TRAIT(has_preincrement, ++);
STATIC_ASSERT((has_preincrement<int>::value));
STATIC_ASSERT((has_preincrement<int*>::value));
STATIC_ASSERT((!has_preincrement<int X::*>::value));
STATIC_ASSERT((has_preincrement<W>::value));
STATIC_ASSERT((has_preincrement<X>::value));
STATIC_ASSERT((!has_preincrement<Y>::value));
// has_predecrement
DEFINE_PREFIX_UNARY_TRAIT(has_predecrement, --);
STATIC_ASSERT((has_predecrement<int>::value));
STATIC_ASSERT((has_predecrement<int*>::value));
STATIC_ASSERT((!has_predecrement<int X::*>::value));
STATIC_ASSERT((has_predecrement<W>::value));
STATIC_ASSERT((has_predecrement<X>::value));
STATIC_ASSERT((!has_predecrement<Y>::value));
// has_postincrement
DEFINE_POSTFIX_UNARY_TRAIT(has_postincrement, ++);
STATIC_ASSERT((has_postincrement<int>::value));
STATIC_ASSERT((has_postincrement<int*>::value));
STATIC_ASSERT((!has_postincrement<int X::*>::value));
STATIC_ASSERT((has_postincrement<W>::value));
STATIC_ASSERT((has_postincrement<X>::value));
STATIC_ASSERT((!has_postincrement<Y>::value));
// has_postdecrement
DEFINE_POSTFIX_UNARY_TRAIT(has_postdecrement, --);
STATIC_ASSERT((has_postdecrement<int>::value));
STATIC_ASSERT((has_postdecrement<int*>::value));
STATIC_ASSERT((!has_postdecrement<int X::*>::value));
STATIC_ASSERT((has_postdecrement<W>::value));
STATIC_ASSERT((has_postdecrement<X>::value));
STATIC_ASSERT((!has_postdecrement<Y>::value));
// Check for private members
STATIC_ASSERT((!has_unary_plus<Z>::value));
STATIC_ASSERT((!is_negatable<Z>::value));
STATIC_ASSERT((!is_dereferenceable<Z>::value));
STATIC_ASSERT((!has_bitwise_not<Z>::value));
STATIC_ASSERT((!has_truth_not<Z>::value));
STATIC_ASSERT((!has_preincrement<Z>::value));
STATIC_ASSERT((!has_predecrement<Z>::value));
STATIC_ASSERT((!has_postincrement<Z>::value));
STATIC_ASSERT((!has_postdecrement<Z>::value));
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