import { Exp, ExpMeta } from "../../exp";
import { Core } from "../../core";
import { Ctx } from "../../ctx";
import { Value } from "../../value";
export declare class Sigma extends Exp {
    meta: ExpMeta;
    name: string;
    car_t: Exp;
    cdr_t: Exp;
    constructor(name: string, car_t: Exp, cdr_t: Exp, meta: ExpMeta);
    free_names(bound_names: Set<string>): Set<string>;
    subst(name: string, exp: Exp): Exp;
    infer(ctx: Ctx): {
        t: Value;
        core: Core;
    };
    sigma_cars_repr(): Array<string>;
    sigma_cdr_t_repr(): string;
    repr(): string;
}