{"ast_node_type":"other","tokens":[{"end":59,"kind":"keyword","start":0,"text":"inner.undo_log.push(UndoLog::PushRegionAssumption);"}]}
        inner.undo_log.push(UndoLog::PushRegionAssumption);
        let mut inner = self.inner.borrow_mut();
        inner.region_assumptions.push(assumption);