{"ast_node_type":"variable","tokens":[{"end":67,"kind":"keyword","start":0,"text":"let"}]}
        let m = self.ir.tcx.parent_module(expr.hir_id).to_def_id();
        let ty = self.typeck_results.expr_ty(expr);
        if ty.is_inhabited_from(self.ir.tcx, m, self.typing_env) {