[Dune] class LocalIndex in dune-localfunctions

[Christian Engwer]

Hi,

> No objections from my side.
> 
> Still as this problem occurs rather frequently as DUNE is growing (I
> has the same problem at least twice and changed to rather unfortunate
> names) I would like to see this issue fixed in all DUNE core modules
> by proper usage of namespaces.
> 
> I therefore would propose to introduce  new namespaces for all core
> modules (Dune::Grid, Dune::Istl, ...) once 1.2 is released.

I think Markus is right. We discussed this issue already several times
and I think the longer wait the bigger the problems will grow.

I think it is clear that we need namespaces, but I think we should
rather use namespaces for interfaces than for modules, like I think
the file hierarchy should be based on interfaces and not modules.

If the module supergrid wants to implement the grid interface I think
this module should use the namespace grid and it should be used by
including <dune/grid/supergrid>, even if it is in seperate module. In
this situation I prefer thinking in concepts rather than in tarballs.

I know that other people might see this differently, thus I posted my
suggestion and wait for the discussion.

Christian