[Dune] Returning Geometries As Objects

[Christian Engwer]

OK Martin,

> first of all, your objection is noted and I will not merge the
> branch before the issue is decided upon.
> 
> However, I think this issue does not just concern the grid
> implementors. It might also have a performance impact on existing
> codes. Currently, it is usually ok to fetch the geometry multiple
> times, because the entity can ensure that it is built up only once.

so perhaps I should relax my objection a little bit. We should not
release before this discussion is settled.
 
> Therefore, I think that a formal vote on the lifetime issue is in
> order (that's why I wanted to postpone it until the next meeting).
> 
> Since you are pressing the issue, I think we should split up the
> issues a little. For example:
> 
> (a) Should we postpone the merge?
> (b) Should we decide on the lifetime issue now or later?
> (c) May the lifetime be limited (by entity / intersection) or not?
> (Maybe capability?)
> (d) Should the lifetime issue be a showstopper for the next release
> (i.e., no transition phase)?
> (e) Should we make another release before we merge?
> 
> I think postponing the merge will increase maintenance costs and
> slow down development, so I'd like the merge to happen soon.

I fully support you. I also would like to see a quick merge, but I
would like to avoid unnecessary problems/confusion in a release.

> Moreover, I also think there will be a lively discussion of (c), so
> I don't know whether deciding now makes sense.
> 
> What are the opionions of the other developers?

I'm curious ;-)

Christian