import type { Sourceable } from "../util/source.js";
import type { SchemaOptions } from "./Schema.js";
import { Schema } from "./Schema.js";
/** Allowed options for `ThroughSchema` */
export interface ThroughSchemaOptions<T> extends SchemaOptions {
    source: Schema<T>;
}
/** Schema that passes through to a source schema. */
export declare abstract class ThroughSchema<T> extends Schema<T> implements Sourceable<Schema<T>> {
    readonly source: Schema<T>;
    constructor({ source, ...options }: ThroughSchemaOptions<T>);
    validate(unsafeValue: unknown): T;
}