syntax_data: {"ast_node_type":"other","tokens":[{"end":84,"kind":"keyword","start":0,"text":"///"}]}
source_snippet:     /// The `disambiguator` field is set by `update_disambiguator` when two distinct
context_before:     ///
context_after:     /// `ExpnId`s would end up with the same `Fingerprint`. Since `ExpnData` includes