Arkadiy Vertleyb writes:

Sorry to repeat this question, but I think I am missing somehing here:

Do I understand correctly that it's not possible in the current version of MPL to use mpl::vector of a size larger than 50?

It is possible. As I tried to explain in my previous reply, you can pre-generate the coressponding headers up to whatever limit you choose. You can also generate the sequence "on the fly", although that's less efficient.

If this is not correct, what exactly do I have to do to use, for example, mpl::vector97<...>?

#include "boost/mpl/vector/vector50.hpp" #include "boost/mpl/aux_/config/vector.hpp" #include "boost/mpl/aux_/config/ctps.hpp" #include "boost/preprocessor/iterate.hpp" #include "boost/config.hpp" namespace boost { namespace mpl { #define BOOST_PP_ITERATION_PARAMS_1 \ (3,(51, 100, "boost/mpl/vector/aux_/numbered.hpp")) #include BOOST_PP_ITERATE() }}

If this _is_ correct, I would like to make a feature request for it to be increased, since the limit of 50 doesnt seem to be high enough (I am making this statement in conjunction with the need of my typeof emulation lib, but I am kind of surprized this question hasn't yet popped up in other contexts, or has it?).

We are using sequences of ~70 elements here at work (mostly in context of FSMs), but then we simply pre-generate them locally. Increasing the default limit to, let's say, 100 elements means plus ~120 KB to the size of the distribution, and I'm not sure the need is widespread enough to make everybody pay for it.

In particular, isn't it possible to just get it fully controlled by BOOST_MPL_LIMIT_VECTOR_SIZE without any limitations whatsoever?

Once again, tweaking BOOST_MPL_LIMIT_VECTOR_SIZE is a dubious practice. You can get as long of a sequence as you want with the technique demostrated in the example above, with a caveat that it's going to be less efficient than using pre-generated headers. -- Aleksey Gurtovoy MetaCommunications Engineering