import type { ChartKey } from './types.js';
export type StackOrder = 'input' | 'ascending' | 'descending' | 'inside-out' | readonly ChartKey[];
export type StackOffset = 'diverging' | 'normalize' | 'center' | 'wiggle';
export interface StackAnchor {
    /** Series whose interval contains the zero anchor. */
    series: ChartKey;
    /** Position within that interval: zero is its start and one is its end. */
    fraction?: number;
}
export interface StackOptions {
    order?: StackOrder;
    offset?: StackOffset;
    reverse?: boolean;
    /** Translate each position so a point within one series lands on zero. */
    anchor?: StackAnchor;
}
export interface StackLayout extends StackOptions {
    readonly type: 'stack';
}
export declare function stack(options?: StackOptions): StackLayout;