[Boost-users] Nullary metafunction

Subject: [Boost-users] Nullary metafunction
From: er (erwann.rogard_at_[hidden])
Date: 2009-02-03 15:13:32

Hi All,

I'm looking for template<typename> class F such that

F<T>::type is T::type if it exists, T itself otherwise.

I was hoping apply<T>::type would work, by analogy with the well known 
example apply<std::vector<_>,X>::type, but apparently not.