syntax_data: {"ast_node_type":"other","tokens":[{"end":88,"kind":"keyword","start":0,"text":"scrutinee.map(|scrut|"}]}
source_snippet:             scrutinee.map(|scrut| self.is_known_valid_scrutinee(scrut)).unwrap_or(true);
context_before:         let known_valid_scrutinee =
context_after:         PatCtxt {