David Abrahams wrote:
on Thu Oct 02 2008, "Christian Holmquist" <c.holmquist-AT-gmail.com> wrote:
2008/10/1 Emil Dotchevski <emil@revergestudios.com>
So, at least I need to include alignment_of.hpp which is so heavy it practically nullifies my efforts to pimpl the U type away in the cpp.
Have a look at boost/intrusive/detail/mpl.hpp, there's a alignment_of with the following comment
I would prefer to fix this dependency problem. AFAICT it only exists for VC6/7 support of mpl lambda expressions with boost type traits. Is this the only trait that exhibits that level of dependency?
I agree fixing alignment_of is the way to go and type_traits utilities need some work to simplify dependencies. For Intrusive I wanted to minimize nearly all external dependencies so I just took alignment_of code and simplified it. This simple code should work for most compilers: #include <cstddef> template <typename T> struct alignment_of; template <typename T> struct alignment_of_hack { char c; T t; alignment_of_hack(); }; template <unsigned A, unsigned S> struct alignment_logic { static const std::size_t value = A < S ? A : S; }; template< typename T > struct alignment_of { static const std::size_t value = alignment_logic < sizeof(alignment_of_hack<T>) - sizeof(T) , sizeof(T) >::value; }; I don't think we need to include <boost/config.hpp> (which includes some std header to detect std library configuration). Regards, Ion