Viewing file:  variadic-ex13.C (1.3 KB) -rw-r--r--
Select action/file-type:
 (+) |  (+) |  (+) | Code (+) | Session (+) |  (+) | SDB (+) |  (+) |  (+) |  (+) |  (+) |  (+) |
// { dg-do compile { target c++11 } }
template<typename T, typename U> struct is_same {
static const bool value = false;
};
template<typename T> struct is_same<T, T> {
static const bool value = true;
};
template<typename...> struct Tuple {};
template<typename T1, typename T2> struct Pair {};
template<typename... Args1>
struct zip {
template<typename... Args2>
struct with {
typedef Tuple<Pair<Args1, Args2>...> type; // { dg-error "mismatched argument pack" }
};
};
static_assert
(is_same<zip<short, int>::with<unsigned short, unsigned>::type,
Tuple<Pair<short, unsigned short>, Pair<int, unsigned> > >::value,
"zip");
typedef zip<short>::with<unsigned short, unsigned>::type T2; // error: different number of arguments specified
// for Args1 and Args2
template<typename... Args> void f(Args...);
template<typename... Args> void g(Args... args)
{
f(const_cast<const Args*>(&args)...); // okay: ``Args'' and ``args'' are expanded
f(5 ...); // { dg-error "contains no parameter packs" }
f(args); // { dg-error "5:parameter packs not expanded" }
// { dg-message "args" "note" { target *-*-* } .-1 }
f(h(args...) + args...); // okay: first ``args'' expanded within h, second ``args'' expanded within f.
}
|
