[dune-pdelab] Variadic Templates

[Christian Engwer]

And just for the record, the first error:

test-composed-iis-gfs.cc:73:   instantiated from here
../../../dune/pdelab/gridfunctionspace/compositegridfunctionspace.hh:75: error: no type named 'Ordering' in 'struct Dune::PDELab::TypeTree::EmptyNode'

we might work around this problem by adding some selector structs, but
we need different structs for each type we query and we have the
problem with member access.

For variadic templates the problem doesn't occure, as only valid
parameters are accessed.

Christian

On Fri, Jun 10, 2011 at 07:59:23PM +0200, Christian Engwer wrote:
> Dear all,
> 
> I experienced some problems when trying to compile my pdelba code with
> a g++-4.2.
> 
> The problem are the DUNE_TYPETREE_COMPOSITENODE macros. Macros like
>  * DUNE_TYPETREE_COMPOSITENODE_CHILDTYPES_NESTED_TYPE
>  * DUNE_TYPETREE_COMPOSITENODE_CHILDTYPES_NESTED_STATIC_MEMBER
>  * DUNE_TYPETREE_COMPOSITENODE_CHILDVARIABLES_MEMBER
> try to access members or typedefs of childnodes. This fails for all
> childs of type EmptyNode. I couldn't come up with a quick solution.
> 
> Does anyone of you have a good idea?
> 
> Currently ComposityNodes are not fully usable with non-variadic
> compilers.
> 
> You can reproduce the problem with g++-4.2 and running "make check" in
> dune-pdelab.
> 
> Christian
> 
> _______________________________________________
> dune-pdelab mailing list
> dune-pdelab at dune-project.org
> http://lists.dune-project.org/mailman/listinfo/dune-pdelab
>