/**
 * Convenience method to build a d3 arc
 *
 * The `d` attribute of the SVG path element expects a string | undefined
 * while the arc returns string | null. This method converts nulls to undefined
 *
 * @param innerRadius - Arc inner radius
 * @param outerRadius - Arc outer radius
 * @param startAngle - Arc start angle
 * @param endAngle - Arc end angle
 */
export declare const buildArc: (innerRadius: number, outerRadius: number, startAngle: number, endAngle: number) => string | undefined;