From: John Maddock (john_at_[hidden])
Date: 2005-01-02 11:01:08
>> Any thoughts from the type_traits authors?
>
> I think decayed is an excellent trait. Your implementation should be
> modified to also take care of functions converting into function pointers
> though. It's a shame about the const qaulifier in your example make_pair
> messing up the int[10] conversion to int*.
I agree that it should work for function to function-pointer conversions as
well.
I've attached a slightly improved version that gets your non-const make_pair
working, also uses remove_bounds rather than the range lib traits (just to
keep things in the type_traits family).
Not sure about the "decayed" name, but I can't think of anything better
right now.
> This is a characteristic of pair, not make_pair. And it could be disabled
> by restricting the member template constructor in:
>
> template <class T1, class T2>
> struct pair {
> typedef T1 first_type;
> typedef T2 second_type;
>
> T1 first;
> T2 second;
> pair();
> pair(const T1& x, const T2& y);
> template<class U, class V> pair(const pair<U, V> &p);
> };
>
> such that is_convertible<U, T1> and is_convertible<V, T2>, which is a
> change I would support.
If we do that, then we should do the same for the tuple constructors as
well.
John.