ForEach activity template parameter from anchor

[adrienmaillard]

Resolves #443
Resolves #445

• Review: By commit
• Merge strategy: Merge (no squash)

Description

Features

• The parameters in activity templates passed to a coexistence goal can now be assigned to values from the anchoring activity. Approach here is similar to the ForEachActivity pattern where an alias is defined for the coexistence goal and the activity template is a function of an ActivityInstance (from the constraints eDSL) with this alias as a parameter. This allows to express the reference to the anchoring activity to the backend and to evaluate expressions.
• More generally, the parameters in activity templates can now be assigned to expressions producing a parameter of the desired type. And allow mixed definition in the case of complex data types (a subfield of a subfield can be an expression while the rest stay absolute values). Commit 3 add the building blocks for hierarchy of expressions. What happen is that even if the user is providing an absolute value, the activity template constructor is turning it into an Expression that will be evaluated. Activity template do not directly contain SerializedValue anymore.
• The valueAt(profile, spans):DiscreteProfile is a new expression returning the value of a profile at a specific time. In this case, the passed spans must be a single instant. I believe this solves Choose the parameter of a “to be scheduled activity” based on a resource #445.

Fixes/changes:

• AssignGaps now evaluates on the forever horizon.
• Discrete and Real activity parameters expressions are defined on the forever horizon. Queried at a time outside the activity bounds, they can return the desired parameter. This allows instantiating a new activity that is not overlapping with an anchoring activity but references a parameter of the anchor activity.
• ActivityInstance (in scheduler-driver) has been refactored into a record.
• Obsolete constraints have been removed and replaced with appropriate global constraints
• CoexistenceGoal now takes an Expression<Spans> as input
• ActivityExpression now implements Expressions<Spans> so it can be used by CoexistenceGoal
• Because CoexistenceGoal takes an Expression<Spans>, AerieLander tests have been commented. The constraints does not have the necessary expressive power yet to express what was expressed in these tests.

Verification

A few tests were added but more are needed. I just want this PR to start.

Documentation

Probably quite a lot of scheduling doc has to be updated.

Future work

• Better representation of timepoints in the eDSL (some kind of DurationExpression) instead of Spans.
• ?

[camargo]

@adrienmaillard provided the following examples for the Banananation model:

export default () =>
  Goal.CoexistenceGoal({
    forEach: ActivityExpression.ofType(ActivityTypes.GrowBanana),
    activityTemplate: growBananaActivity =>
      ActivityTemplates.PickBanana({ quantity: growBananaActivity.parameters.quantity }),
    startsAt: TimingConstraint.singleton(WindowProperty.END).plus(Temporal.Duration.from({ minutes: 5 })),
  });

export default () =>
  Goal.CoexistenceGoal({
    forEach: ActivityExpression.ofType(ActivityTypes.GrowBanana),
    activityTemplate: growBananaActivity =>
      ActivityTemplates.ChangeProducer({
        producer: Discrete.Resource('/producer').valueAt(growBananaActivity.span().starts()),
      }),
    startsAt: TimingConstraint.singleton(WindowProperty.END).plus(Temporal.Duration.from({ minutes: 5 })),
  });

[JoelCourtney]

Here's a review of the constraints side of things. I won't have time to go through all of the scheduler things today. Nice work!

[JoelCourtney]

noice