export type HeaderOrParamValue = Array<string | {}> | string | {} | null | undefined;
/**
 * Function that accommodates flattening headers or query params, since they can
 * be either string or string[]. Function defaults to picking the first element
 * of an array, but can also be set to pick the last element with the optional
 * useLast parameter. For any query params that are more complex (objects, etc),
 * this will return undefined; this behavior is only relevant in server
 * contexts.
 *
 * @param {string|string[]|object|object[]|undefined} value a header or query param value
 * @param {boolean} [useLast=false] optional parameter to use last element if array
 * @return {string|undefined} the flattened value
 */
export declare function flattenHeaderOrParam(value: HeaderOrParamValue, useLast?: boolean): string | undefined;
//# sourceMappingURL=index.d.ts.map