/**
 * Utility to add a performance marker.
 *
 * @param markName
 */
export declare function mark(markName: string): void;
/**
 * Utility to measure performance between the start and end markers.
 *
 * @param comment
 * @param startMark
 * @param endMark
 */
export declare function measure(comment: string, startMark: string, endMark: string): void;
/**
 * Utility to place end marker and measure performance.
 *
 * @param comment
 * @param startMark
 * @param endMark
 */
export declare function markEndAndMeasure(comment: string, startMark: string, endMark: string): void;