Re: [boost] Is type list defined in boost

17 Jul 2007

      On 7/17/07, Peng Yu <pengyu.ut@gmail.com> wrote:
...
On 7/16/07, Mathias Gaunard <mathias.gaunard@etu.u-bordeaux1.fr> wrote:
...
Peng Yu wrote:
...
I've seen typelist somewhere. I'm wondering if it is defined in boost?
Boost has better than that, it has the Boost Meta-Programming Library
(MPL) that contains various data structures and algorithms around types.
Hi,
I saw list in mpl. But I'm not familiar with it yet. Would you please
show me how to do the same thing in mpl as that in my original email?
Hi,

I forgot mention that I use type_list in the following code. I'm
wondering how to replace type_list with mpl::list.

Thanks,
Peng

class A;
class B;

typedef type_list<A, type_list<B> > AB;

class base {
  public :
    virtual ~base() {}
    virtual void accept(base& b) = 0 ;
};

template <typename TL, typename Base>
class visitor : public visitor<typename TL::tail, Base> {
  public :
    virtual ~visitor() { }
    virtual void visit(typename TL::head &) {
       std::cout << __PRETTY_FUNCTION__ << std::endl;
    }
    using visitor<typename TL::tail, Base>::visit;
//    no visit() function defined for visitor<list_end, Base>
// is there any way to make the above using statement conditional?
// (if the base class is visitor<list_end, Base>, not to use this statement.)
};

template <typename Base>
class visitor<list_end, Base> : public Base {
  public :
    virtual ~visitor() { }

};