syntax_data: {"ast_node_type":"other","tokens":[{"end":46,"kind":"keyword","start":0,"text":"if"}]}
source_snippet:                 if !self.seen.insert(def_id) {
context_before:             ty::Alias(ty::Free, alias_ty) if let Some(def_id) = alias_ty.def_id.as_local() => {
context_after:                     return;