id,summary,reporter,owner,description,type,status,milestone,component,version,severity,resolution,keywords,cc
10403,fusion make_map metafunction,Wojciech Mamrak <wmamrak@…>,Joel de Guzman,"Hello,

It seems documentation is out-of-sync with implementation of fusion's make_map metafunction, and also the new implementation (using variadic templates) is inconsistent with previous ones.

The docs [1] say:
result_of::make_map<int, double, char, double>::type

make_map is implemented as a metafunction class, i.e. it does not have a nested type typedef:
        template <typename ...Key>
        struct make_map
        {
            template <typename ...T>
            struct apply
            {
                typedef map<
                    fusion::pair<
                        Key
                      , typename detail::as_fusion_element<T>::type
                    >...>
                type;
            };
        };

so the proper ""call"" would be:
result_of::make_map<int, double>::apply<char, double>::type

From this I conclude it is not only a documentation error, but also api breach. Presumably it got unnoticed since make_map function is not using make_map metafunction anymore (as opposed to what the docs claim [2]).

regards


[1] http://www.boost.org/doc/libs/1_56_0/libs/fusion/doc/html/fusion/container/generation/metafunctions/make_map.html
[2] http://www.boost.org/doc/libs/1_56_0/libs/fusion/doc/html/fusion/container/generation/functions/make_map.html",Bugs,closed,To Be Determined,fusion,Boost 1.56.0,Problem,fixed,fusion make_map,