Expand description
Plan representation.
A plan is a totally-ordered sequence of grounded operator applications
whose execution transforms the initial state into a goal-satisfying state.
Plans here are sequential — there is no partial ordering or parallelism.
They are produced by the planners in crate::search.
The Plan struct carries two invariants:
stepsrecords which grounded operators to apply and in what order.costis the numeric sum of the executed operators’ costs, so empty plans always havecost == 0.0.
The Display impl on Plan emits a PDDL-style
human-readable format.