// DR 339 // // Test of the use of the new and new[] operators 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(new T, 0) > 0), yes_type>::type check_new(int); template no_type check_new(...); template struct has_new { static const bool value = (sizeof(check_new(0)) == sizeof(yes_type)); }; template typename enable_if<(sizeof((new T(create_a())), 0) > 0), yes_type>::type check_new_one_arg(int); template no_type check_new_one_arg(...); template struct has_new_one_arg { static const bool value = (sizeof(check_new_one_arg(0)) == sizeof(yes_type)); }; template typename enable_if<(sizeof(new T[N], 0) > 0), yes_type>::type check_array_new(int); template no_type check_array_new(...); template struct has_array_new { static const bool value = (sizeof(check_array_new(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 { X(int); }; struct Y { int foo; }; STATIC_ASSERT((has_new::value)); STATIC_ASSERT(!(has_new::value)); STATIC_ASSERT((has_new_one_arg::value)); STATIC_ASSERT((has_new_one_arg::value)); STATIC_ASSERT(!(has_new_one_arg::value)); STATIC_ASSERT((has_array_new::value)); STATIC_ASSERT(!(has_array_new::value)); STATIC_ASSERT((has_array_new::value));