{"ast_node_type":"function","tokens":[{"end":84,"kind":"keyword","start":0,"text":"fn"}]}
    fn new(ir: &'a mut IrMaps<'tcx>, body_owner: LocalDefId) -> Liveness<'a, 'tcx> {
impl<'a, 'tcx> Liveness<'a, 'tcx> {
        let typeck_results = ir.tcx.typeck(body_owner);