[boost] [mpl] and_<true_> returns false

Subject: [boost] [mpl] and_<true_> returns false
From: Agustín K-ballo Bergé (kaballo86_at_[hidden])
Date: 2013-09-18 19:33:31

The following snippet fails to compile (tested with 1.54.0 and trunk, 
several compilers),

#include <boost/mpl/and.hpp>
#include <boost/mpl/bool.hpp>
#include <boost/mpl/or.hpp>

int main() {
     using namespace boost::mpl;
     static_assert(and_<true_>::value, "U KID?"); //this one fires
     static_assert(or_<true_>::value, "U KID?"); //this one is ok
}

This issue actually showed up in a variadic template scenario. Is this a 
bug? I feel like I'm doing something really wrong...

I guess one may not call `and_` with less than two arguments. If that's 
the case, it would be helpful if it would be impossible to instantiate 
it with a single argument.

Regards,
-- 
Agustín K-ballo Bergé.-
http://talesofcpp.fusionfenix.com