/**
 * Efficiently checks if a React directive (e.g., "use server", "use client")
 * is present in the code. Optimized for performance with a two-step approach:
 * 1. Quick string search to see if directive exists anywhere
 * 2. Line-by-line check only if the directive might be present
 */
export declare function hasDirective(code: string, directive: string): boolean;