use ;
use Arc;
/// A [`TraversalModelService`] is a persistent builder of [TraversalModel] instances.
/// Building a [`TraversalModelService`] may be an expensive operation and often includes
/// file IO on the order of the size of the road network edge list.
/// The service then builds a [TraversalModel] instance for each route query.
/// [`TraversalModelService`] must be read across the thread pool and so it implements
/// Send and Sync.
///
/// [TraversalModel]: compass_core::model::traversal::model::TraversalModel