[Boost-users] mpl::vector -> boost::tuple

From: Markus Werle (numerical.simulation_at_[hidden])
Date: 2004-06-29 06:08:02

Hi!

The example in libs/mpl/example/tuple_from_list.cpp
and gen_linear_hierarchy from 
http://aspn.activestate.com/ASPN/Mail/Message/boost/1166644

    template< typename Types, typename Unit, typename Root = mpl::none > 
    struct gen_linear_hierarchy
    {
        typedef typename mpl::fold<Types,Unit,Root> ::type type; // here
    };

    /* usage example:
    template< class Base, class T > 
    struct EventHander : public Base
    {
        virtual void OnEvent(T& obj, int eventID) = 0;
    };

    typedef gen_linear_hierarchy<
          mpl::list<Window,Button,ScrollBar> 
        , EventHander<_1,_2> 
        > ::type v;
    */

all seem to me work fine with default constructible types.
What I need is a type generator which provides a constructor, such that
code like this one works for mpl::vectors (or other mpl::sequences) 
with arbitrary length:

-------------
class C { C(std::string const & gaga) {} };

struct gen_linear_hierarchy_with_constructor
// your idea missing here
{
// and here
};

typedef 
gen_linear_hierarchy_with_constructor<mpl::vector<C, C> >::type mytuple;

mytuple mt("test", "Thanks for your help");
------------------

Markus

P.S.: David and Aleksey, if you read this here: I could not find your
"coming soon" book at awprofessional.com. What's the current state 
of the book I wait for so long already ...