{"ast_node_type":"variable","tokens":[{"end":62,"kind":"keyword","start":0,"text":"let"}]}
        let rest_args = (0..rest_count).map(|_| rest_ll_unit);
            self.prefix.iter().flat_map(|option_reg| option_reg.map(|reg| reg.llvm_type(cx)));
        let args: Vec<_> = prefix_args.chain(rest_args).collect();