import type { ChartColorOptions, ChartKey, ChartTheme, ResolvedColorScale } from './types.js';
export declare function createColorScale(values: readonly unknown[], options: ChartColorOptions | undefined, theme: ChartTheme): ResolvedColorScale;
export declare function isChartKey(value: unknown): value is ChartKey;
export declare function valueKey(value: unknown): string;
/** Orders ChartKey values independently from their collision-safe identity. */
export declare function compareChartKey(left: ChartKey | null, right: ChartKey | null): number;