import { Exp, ExpMeta } from "../../exp";
import { Core } from "../../core";
import { Ctx } from "../../ctx";
import { Value } from "../../value";
import * as Exps from "../../exps";
export declare class NilCls extends Exps.Cls {
    meta: ExpMeta;
    field_names: Array<string>;
    constructor(meta: ExpMeta);
    free_names(bound_names: Set<string>): Set<string>;
    subst(name: string, exp: Exp): Exps.Cls;
    fields_repr(): Array<string>;
    repr(): string;
    infer(ctx: Ctx): {
        t: Value;
        core: Core;
    };
}