{"ast_node_type":"variable","tokens":[{"end":91,"kind":"keyword","start":0,"text":"let"}]}
                let ast::PatKind::Guard(_, mut cond) = subpat.kind else { unreachable!() };
                let ast::PatKind::Paren(subpat) = pat.kind else { unreachable!() };
                self.psess.gated_spans.ungate_last(sym::guard_patterns, cond.span);