{"ast_node_type":"other","tokens":[{"end":61,"kind":"keyword","start":0,"text":"impl<'tcx>"}]}
impl<'tcx> Rollback<UndoLog<'tcx>> for InferCtxtInner<'tcx> {
/// The Rollback trait defines how to rollback a particular action.
    fn reverse(&mut self, undo: UndoLog<'tcx>) {