syntax_data: {"ast_node_type":"other","tokens":[{"end":53,"kind":"keyword","start":0,"text":"Some(GenericArgKind::Lifetime(r1))"}]}
source_snippet:             Some(GenericArgKind::Lifetime(r1)) => r1,
context_before:         match self.map.get(&r.into()).map(|arg| arg.kind()) {
context_after:             Some(u) => panic!("region mapped to unexpected kind: {u:?}"),