{"ast_node_type":"other","tokens":[{"end":73,"kind":"keyword","start":0,"text":"debug!(\"RegionConstraintCollector:"}]}
        debug!("RegionConstraintCollector: rollback_to({:?})", snapshot);
    pub(super) fn rollback_to(&mut self, snapshot: RegionSnapshot) {
        self.storage.any_unifications = snapshot.any_unifications;