/**
 * `StructError` objects are thrown (or returned) by Superstruct when its
 * validation fails. The error represents the first error encountered during
 * validation. But they also have an `error.failures` property that holds
 * information for all of the failures encountered.
 */
export declare class StructError extends TypeError {
    branch: Branch;
    failures: Failure[];
    path: Path;
    type: string | undefined;
    value: any;
    [key: string]: any;
    constructor(failures: Failure[]);
}
/**
 * `Path` arrays specify a nested value's location in a root object or array.
 *
 * ```js
 * ['user', 'address', 'city']
 * ['nodes', 1, 'nodes', 0, 'text']
 * ```
 */
export declare type Path = Array<number | string>;
/**
 * `Branch` arrays contain each value following a path down from the root.
 *
 * ```js
 * [root, ..., parent, value]
 * ```
 */
export declare type Branch = Array<any>;
/**
 * `Failure` objects represent a specific failure in validation. They are plain
 * objects that can be turned into real `StructError` when needed.
 *
 * ```js
 * {
 *   type: 'number',
 *   value: 'invalid',
 *   path: [1],
 *   branch: [
 *     [1, 'invalid', 2],
 *     'invalid',
 *   ]
 * }
 */
export declare type Failure = {
    /**
     * The branch of values following a path down from the root.
     */
    branch: Branch;
    /**
     * The path of indices to retrieve the failing value from the root.
     */
    path: Path;
    /**
     * The failing value.
     */
    value: any;
    /**
     * The expected type description of the failing value, or `undefined` if it
     * didn't have an expected type.
     */
    type: string | undefined;
    /**
     * Failures can also be augmented with any of your on custom properties.
     */
    [key: string]: any;
};