{"ast_node_type":"function","tokens":[{"end":46,"kind":"keyword","start":0,"text":"fn"}]}
    fn decode(decoder: &mut D) -> &'tcx Self {
impl<'tcx, D: TyDecoder<'tcx>> RefDecodable<'tcx, D> for ty::List<Ty<'tcx>> {
        let len = decoder.read_usize();