/**
 * Performs a deep structural equality check across all provided arguments.
 * Returns true only if every argument is deeply equal to every other argument.
 * Handles primitives, arrays, and plain objects (JSON-like) recursively.
 *
 * Non-plain objects (Set, Map, Date, etc.) are compared by reference only,
 * since Object.keys() does not enumerate their contents.
 *
 * @param args - Two or more values to compare for deep equality
 * @returns True if all arguments are deeply equal
 *
 * @example
 * ```ts
 * deepEqual({ a: 1 }, { a: 1 })           // true
 * deepEqual([1, 2], [1, 2], [1, 2])       // true
 * deepEqual({ a: 1 }, { a: 2 })           // false
 * ```
 */
export declare function deepEqual(...args: unknown[]): boolean;