import { Ctx } from "../ctx";
import { Core } from "../core";
import { Value } from "../value";
import { Narrator } from "../narrator";
import pt from "@cicada-lang/partech";
export interface ExpMeta {
    span?: pt.Span;
}
export interface ElaborationOptions {
    narrator?: Narrator;
}
export declare abstract class Exp {
    meta?: ExpMeta;
    abstract free_names(bound_names: Set<string>): Set<string>;
    abstract subst(name: string, exp: Exp): Exp;
    abstract repr(): string;
    check?(ctx: Ctx, t: Value, opts?: ElaborationOptions): Core;
    infer?(ctx: Ctx, opts?: ElaborationOptions): {
        t: Value;
        core: Core;
    };
}