Feature request: allow additional allocation criteria besides student preference

[robelko]

While doing the seat assignments, we need to give higher priority to students from higher study semesters not just the preferences provided by students. As a matter of fact, in some situations, we do not want students to give any preferences, but for example give priority for assignments where there are more places available than students requesting a seat. Prioritizing higher semesters can be done fairly easily as I imagine -- the program gets a list of study semesters as entered by students, then does assignments looping through the list from highest to lowest (or reverse if that is desired), getting a list of students for a given study semester and doing the assignments as it does now, then proceeding to the next semester.

Now, I would not want the module to get overly complicated with many options and variations. I would strongly suggest to use the approach taken by the assignment module -- a module which is a set of submodules with a common core. This approach would allow to more easily support various assignment strategies. For example, the hereby requested assignment with additional criterium would be a separate mode (submodule) from the basic assignment as it is now. The mode of assigning without student priorities could be another submodule. Allocation based on groups (as requested by someone a while ago) could be yet another submodule.

While this approach would initially require some effort to adjust the structure of the module, I believe that it will make it easier to expand and support alternative allocation strategies in the future. I bet we will see increasing need for that and this module might become one of the important components of Moodle.