Re: [Boost-users] [Proto] Stuck turning a complex gramamr action to a primitive trasnform

28 Oct 2009


      joel wrote:
...
I tried to turn a complex grammar transform
:
struct grammar :
or_< ...
,bp::when< bp::nary_expr< bp::_, bp::vararg< grammar > >
                         , bp::_default< grammar >
                           (
_bp::functional::unpack_exprbp::tag::function(
                                       push_front( bp::_
                                                 , bp::_make_terminal
                                                   (
                                                      some_type< 
bp::tag_ofbp::_ >()
                                                   )
                                                 )
                                      )
                           )
                         >
into a single primitive transform but I end up stuck cause it seems some 
of those transform (make_terminal) don't follow
the classic proto::result_of/proto namespace acces to compute it's 
return type and calling it.
I don't know what you mean. Are you referring to the fact that 
_make_terminal is not a primitive transform? It is a callable function 
object. Unfortunately, the _make_terminal name follows Proto's naming 
conventions for primitive transforms, even though it isn't. Is that what 
has thrown you off?

-- 
Eric Niebler
BoostPro Computing
http://www.boostpro.com