import { Fail, Runtype } from './runtype';
/**
 * Create a validation error for custom runtypes
 */
export declare function createError(msg: string): Fail;
/**
 * Construct a custom runtype from a validation function.
 */
export declare function runtype<T>(fn: (v: unknown) => T | Fail): Runtype<T>;
/**
 * Explicit validation result containing the wrapped result or error.
 */
export declare type ValidationResult<T> = {
    ok: true;
    result: T;
} | {
    ok: false;
    error: Fail;
};
/**
 * Execute a runtype but do not throw Errors
 *
 * Return a ValidationResult instead.
 * When its an Error, use `getFormattedError` on it to get a well formatted
 * message for logging or reporting.
 *
 * Useful when writing your own runtypes and when the bad performance of
 * exceptions and try-catch for error handling is of concern.
 */
export declare function use<T>(r: Runtype<T>, v: unknown): ValidationResult<T>;