{"ast_node_type":"variable","tokens":[{"end":75,"kind":"keyword","start":0,"text":"let"}]}
            let mut err = self.dcx().struct_span_err(self.token.span, msg);
            let msg = format!("expected `where` or `{{` after union name, found {token_str}");
            err.span_label(self.token.span, "expected `where` or `{` after union name");