Re: Introspect public member functions
On 2014-07-15 09:04, Lorenzo Caminiti wrote:
I am trying to write a C++11 meta-function that returns true if and
only if a class T has a public member function f (and false if either
T::f does not exist, or it is private, or it is protected).
Is this possible?
Yes.
The code below works correctly on CLang++ (3.1) but the
private/protected T::f raises compiler errors on G++ (4.5.3)...
Who is correct with respect to the C++11 standard?
This should work, so Clang looks right here.
The following alternative code also works gcc (but you need a version
greater than 4.8):
struct has_public_f_impl
{
template<class T, class = decltype(std::declval<T&>().f())>
static std::true_type check(int);
template<class>
static std::false_type check(...);
};
template<class T>
struct has_public_f : decltype(has_public_f_impl::check<T>(0))
{
};
HTH & Greetings from Bremen,
Daniel Kr?gler
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