{"ast_node_type":"other","tokens":[{"end":88,"kind":"keyword","start":0,"text":"impl<D:"}]}
impl<D: Decoder, Prov: Provenance + Decodable<D>> Decodable<D> for ProvenanceMap<Prov> {
// for some particular `D`/`S`.
    fn decode(d: &mut D) -> Self {