/**
 * Cache policy for which lookups.
 */
export declare const enum WhichCachePolicy {
    /**
     * Use cached result if available.
     */
    Cached = 0,
    /**
     * Bypass cache and perform a new lookup.
     */
    Bypass = 1,
    /**
     * Always update cache.
     */
    Fresh = 2,
    /**
     * Read-only, serves from cache if present, but doesn't write.
     */
    ReadOnly = 3
}
export interface WhichOptions extends Bun.WhichOptions {
    /**
     * Cache policy for the lookup.
     * Defaults to `WhichCachePolicy.Fresh`.
     */
    cache?: WhichCachePolicy;
}
export declare const whichFresh: typeof Bun.which;
/**
 * Locate binary on PATH (with flexible caching).
 *
 * @param command - Binary name to resolve
 * @param options - Bun.WhichOptions plus `cache` control
 * @returns Filesystem path if found, else null
 */
export declare function $which(command: string, options?: WhichOptions): string | null;