/**
 * D3 Array Polyfill - Lightweight array utility functions.
 *
 * This is a drop-in replacement for d3-array, implementing only the methods
 * used in the Vega chart rendering system: min, max, extent, and map.
 *
 * @see VD-5022 - [Zero Dependencies] remove d3 dependency
 */
/**
 * Returns the minimum value in the array.
 * Mimics d3.min().
 *
 * @template T
 * @param {T[]} array - Array of values.
 * @param {Function} [accessor] - Optional accessor function.
 * @returns {number | undefined} The minimum value, or undefined for empty arrays.
 */
export declare function min<T>(array: T[], accessor?: (d: T, i: number) => number): number | undefined;
/**
 * Returns the maximum value in the array.
 * Mimics d3.max().
 *
 * @template T
 * @param {T[]} array - Array of values.
 * @param {Function} [accessor] - Optional accessor function.
 * @returns {number | undefined} The maximum value, or undefined for empty arrays.
 */
export declare function max<T>(array: T[], accessor?: (d: T, i: number) => number): number | undefined;
/**
 * Returns the [min, max] of the array.
 * Mimics d3.extent().
 *
 * @template T
 * @param {T[]} array - Array of values.
 * @returns {[T, T] | [undefined, undefined]} Tuple of [min, max], or [undefined, undefined] for empty arrays.
 */
export declare function extent<T>(array: T[]): [T, T] | [undefined, undefined];
/**
 * Maps each element of the array through a transform function.
 * Mimics d3.map() (the array mapping function from d3-array, not the Map collection).
 *
 * @template T
 * @template U
 * @param {T[]} array - Input array.
 * @param {Function} mapper - Transform function called with (element, index).
 * @returns {U[]} New array of transformed values.
 */
export declare function map<T, U>(array: T[], mapper: (d: T, i: number) => U): U[];