syntax_data: {"ast_node_type":"other","tokens":[{"end":100,"kind":"keyword","start":0,"text":"Some(ty::GenericArgKind::Lifetime(lt))"}]}
source_snippet:                     Some(ty::GenericArgKind::Lifetime(lt)) => self.shift_region_through_binders(lt),
context_before:                 match rk {
context_after:                     Some(other) => self.region_param_expected(data, r, other),