[gecode-users] Idea for extending ViewBrancher

[Felix Brandt]

Hi,

for a recent project I wrote a custom brancher (similar to the
ViewBrancher) that only branches variables within a certain interval.
The variables, which do not intersect the interval, are considered as if
they are already assigned.

In my case I wasn't interested in the values if they did not match the
given interval, but also did not want to add auxiliary variables and
constraints to be able to use standard branchers. Furthermore, I could
not just assign border values without breaking constraints. I assume
that such a brancher can also be advantageous in other setups, where one
wants to apply varying branching strategies to different parts of the
variable domains.

If this idea is of interest for the project, I could try to extend the
current ViewValueBrancher. Right now, I'm not sure where to start.
Probably adapting ViewBrancher<ViewSel>::status(const Space&) is a good
starting point, but it's quite deep in the object hierarchy so I assume
it's not *that* easy. Additionally, inheriting from ViewBrancher seems
to produce a lot of duplicated code (for brancher assembly and strategy
selection). Any suggestions?

Regards,
Felix

PS: If I miss something obvious or this feature is already present, I
would appreciate any hint :-)