Re: [Boost-users] Help with deduced template parameters

From: Peter Dimov (pdimov_at_[hidden])
Date: 2008-06-02 10:38:29

Chris Ross:
>  Forgive me if the answer ends up being strictly C++, rather than
> Boost.  But, I have a template class that I would rather be able to
> deduce it's single [current] template parameter rather than having to
> specify it.  I'm wondering if boost::function or boost::functional might
> make this easier for me to accomplish.

...

> template <typename List>
> class detach_all {
>  public:
>    detach_all(const List &e) : list(e) {}
>    template <class T>
>    void operator ()(T*ent) const
>    {
>        if (dynamic_cast<Messageable*>(ent)) {
>            std::for_each(list.begin(), list.end(),
>              stop_messaging(dynamic_cast<Messageable*>(ent)));
>        }
>    }

struct detach_all
{
    typedef void result_type;

    template<class T, class L>
    void operator()( T * pt, L * pl ) const
    {
        if( Messageable * pm = dynamic_cast<...>( pt ) )
        {
            std::for_each( pl->begin(), pl->end(), 
                stop_messaging( pm ) );
        }
    }
};

int main()
{
    List list;
    mutexed_for_each( boost::bind( detach_all(), _1, &list ) );
}

is one alternative.