{"ast_node_type":"function","tokens":[{"end":67,"kind":"keyword","start":0,"text":"fn"}]}
    fn map_provenance(self, f: impl FnOnce(Prov) -> Prov) -> Self {
    /// Adjust the provenance of the main pointer (metadata is unaffected).
        MemPlace { ptr: self.ptr.map_provenance(|p| p.map(f)), ..self }