Simplify the use case food-packaging

[kentbill]

Why do we need 3 shadow variables in the food packaging example: startCleaningDateTime, startProductionDateTime, and endDateTime? Can we only define startCleaningDateTime as a shadow variable, and the other 2 variables deduced from it:

1. The startProductionDateTime is startCleaningDateTime plus cleaningDuration.
2. The endTime is startProductionDateTime plus the duration of the job.

Did I overlook some situations that have to let startCleaningDateTime and startProductionDateTime be shadow variables?

[ge0ffrey]

That would work too. It's a trade-off.

I think it wrote it this way to make it easier to reuse those values in the UI, without having to calculate them there... Not a good reason :)

Or to avoid the hashmap lookup to calculate the cleaning duration, when endTime is used in the constraint(s). Not sure if that matters much though.

[kentbill]

got it, thank you Geoffrey!