usecrate::plan::concurrent::Pause;usecrate::plan::Plan;/// Trait for a concurrent plan.
pubtraitConcurrentPlan: Plan {/// Return `true`` if concurrent work (such as concurrent marking) is in progress.
fnconcurrent_work_in_progress(&self)->bool;/// Return the current pause kind. `None` if not in a pause.
fncurrent_pause(&self)->Option<Pause>;}