export type HeatmapColumn = {
    type: 'spacer';
} | {
    type: 'column';
    month: number;
    weekIndex: number;
};
/**
 * Builds a list of visual columns for the heatmap. When `splitMonths` is false,
 * there is exactly one column per week. When `splitMonths` is true, weeks that
 * span two months are split into two columns and a spacer column is inserted
 * between different months.
 */
export declare function getColumns(datesRange: (string | null)[][], splitMonths?: boolean): HeatmapColumn[];
export declare function getFirstMonthColumnIndex(columns: HeatmapColumn[], month: number): number;