TypeScript utilities: GUID and deepCopy (clone)

utils.ts

/**
 * Create a GUID
 * @see https://stackoverflow.com/a/2117523/319711
 *
 * @returns RFC4122 version 4 compliant GUID
 */
export const uuid4 = () => {
  return 'xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx'.replace(/[xy]/g, (c) => {
    // tslint:disable-next-line:no-bitwise
    const r = (Math.random() * 16) | 0;
    // tslint:disable-next-line:no-bitwise
    const v = c === 'x' ? r : (r & 0x3) | 0x8;
    return v.toString(16);
  });
};

/**
 * Create a unique ID
 * @see https://stackoverflow.com/a/2117523/319711
 *
 * @returns id followed by 8 hexadecimal characters.
 */
export const uniqueId = () => {
  // tslint:disable-next-line:no-bitwise
  return 'idxxxxxxxx'.replace(/[x]/g, () => ((Math.random() * 16) | 0).toString(16));
};

/**
 * Pad left, default with a '0'
 *
 * @see http://stackoverflow.com/a/10073788/319711
 * @param {(string | number)} n
 * @param {number} width
 * @param {string} [z='0']
 * @returns
 */
export const padLeft = (n: string | number, width: number, z = '0') => {
  n = n + '';
  return n.length >= width ? n : new Array(width - n.length + 1).join(z) + n;
};

/**
 * Deep copy function for TypeScript.
 * @param T Generic type of target/copied value.
 * @param target Target value to be copied.
 * @see Source project, ts-deepcopy https://github.com/ykdr2017/ts-deepcopy
 */
export const deepCopy = <T>(target: T): T => {
  if (target === null) {
    return target;
  }
  if (target instanceof Date) {
    return new Date(target.getTime()) as any;
  }
  if (target instanceof Array) {
    const cp = [] as any[];
    (target as any[]).forEach((v) => { cp.push(v); });
    return cp.map((n: any) => deepCopy<any>(n)) as any;
  }
  if (typeof target === 'object' && target !== {}) {
    const cp = { ...(target as { [key: string]: any }) } as { [key: string]: any };
    Object.keys(cp).forEach(k => {
      cp[k] = deepCopy<any>(cp[k]);
    });
    return cp as T;
  }
  return target;
};