import { ReactNode } from 'react';
/**
 * Flattens nested React children into a single-level array. <br />
 * Preserves keys by concatenating parent keys with child keys. <br />
 * Handles fragments and nested fragments recursively. <br />
 *
 * @param children - The React children to flatten.
 * @param recursionDepth - The maximum depth to recurse into fragments. Default is -1 (infinite).
 * @param keys - The accumulated keys from parent elements.
 * @returns An array of flattened React nodes.
 */
export declare function flattenChildren(children: ReactNode, recursionDepth?: number, keys?: (string | number)[]): ReactNode[];