import type { Context, MiddlewareHandler, Env, ValidationTargets } from "hono";
import type { Infer, Struct, StructError } from "superstruct";
/**
 * A function constructs a Hono response from the given {@link StructError}.
 *
 * @param error The error that occurred while trying to validate a Superstruct schema.
 * @param context The Hono request context.
 * @returns A response, or a promise that resolves with a response.
 */
export type OnError<E extends Env, Path extends string> = (error: StructError, context: Context<E, Path>) => globalThis.Response | Promise<globalThis.Response>;
/**
 * Constructs simple validator middleware for Hono to ensure incoming data matches
 * a given Superstruct schema.
 *
 * @param target The format for which this validator should apply (i.e.
 *  `"json"` or `"form"`)
 * @param struct The Superstruct schema against which the request body
 *  should be strictly validated.
 * @param onError An optional callback to handle the {@link StructError} if
 *  the body could not be validated. This callback will not be called if
 *  the request body passes the schema's validation.
 * @returns Hono middleware that ensures later steps can get valid data
 *  from the request body.
 */
export declare const sValidator: <T extends Struct<any, any>, Target extends keyof ValidationTargets, E extends Env, Path extends string, V extends {
    in: { [K in Target]: Infer<T>; };
    out: { [K_1 in Target]: Infer<T>; };
} = {
    in: { [K_2 in Target]: Infer<T>; };
    out: { [K_3 in Target]: Infer<T>; };
}>(target: Target, struct: T, onError?: OnError<E, Path> | undefined) => MiddlewareHandler<E, Path, V>;