#include <boost/mpl/fold.hpp>
#include <boost/utility/value_init.hpp> 

namespace mpl=boost::mpl;

struct do_until_functor_base
{
  template<typename F>
  bool operator()(F)const{return false;}
};

template<typename Base,typename T>
struct do_until_functor_step:Base
{
  template<typename F>
  bool operator()(F f)const
  {
    if(Base::operator()(f))return true;
    boost::value_initialized<T> t;
    return f(boost::get(t));
  }
};

template<typename Seq>
struct do_until_functor:
  mpl::fold<
    Seq,
    do_until_functor_base,
    do_until_functor_step<mpl::_1,mpl::_2>
  >::type
{};

template<typename Seq,typename F>
bool do_until(F f)
{
  do_until_functor<Seq> d;
  return d(f);
}


/**** testing ****/

#include <boost/mpl/vector.hpp>
#include <boost/type_traits/is_same.hpp>
#include <iostream>

template<typename T>
struct verbose_is_same
{
  template<typename Q>
  bool operator()(Q)const
  {
    static const bool b=boost::is_same<T,Q>::value;
    std::cout<<typeid(Q).name()<<std::endl;
    return b;
  }
};

int main()
{
  typedef mpl::vector<int,char,double,long> v1;
  do_until<v1>(verbose_is_same<double>());
}