[Boost-users] what is template<typename> struct +; ?

Subject: [Boost-users] what is template<typename> struct +; ?
From: Tan, Tom (Shanghai) (TTan_at_[hidden])
Date: 2010-01-24 20:18:17

While trying to read \boost\fusion adapt_struct.hpp and understand the
internals of BOOST_FUSION_ADAPT_STRUCT.
I came across this code:

    namespace boost { namespace mpl  \

    {                                                      \

        template<typename> \

        struct +;    \

 
\

//....

}}

 

Can  anyone please explain what " template<typename>   struct +;    "

means here? I am puzzled how it ever compiles as an operator is used as
a class name.

 

Thanks.