17a18
> #if BOOST_WORKAROUND(__GNUC__, <= 3)
20c21
<     struct name; /* forward decl */                                             \
---
>     struct name; /* forward declaration */                                      \
26c27,28
<         BOOST_PP_CAT(name,Concept)(); /* ctor needed to satisfy gcc-3.4.4 */    \
---
>         /* at least 2.96 and 3.4.3 both need this */                            \
>         BOOST_PP_CAT(name,Concept)();                                           \
30a33,46
> #else
> # define BOOST_concept(name, params)                                            \
>     template < BOOST_PP_SEQ_FOR_EACH_I(BOOST_CONCEPT_typename,~,params) >       \
>     struct name; /* forward declaration */                                      \
>                                                                                 \
>     template < BOOST_PP_SEQ_FOR_EACH_I(BOOST_CONCEPT_typename,~,params) >       \
>     struct BOOST_PP_CAT(name,Concept)                                           \
>       : name< BOOST_PP_SEQ_ENUM(params) >                                       \
>     {                                                                           \
>     };                                                                          \
>                                                                                 \
>     template < BOOST_PP_SEQ_FOR_EACH_I(BOOST_CONCEPT_typename,~,params) >       \
>     struct name                                                                
> #endif