Function randomSlice

src/array.ts:4–17

(arr: T[], num?: number)

 * Array random slice with items count
 */
export function randomSlice<T = any>(arr: T[], num?: number): T[] {
  if (!num || num >= arr.length) {
    return arr.slice();
  }
  const index = Math.floor(Math.random() * arr.length);
  const a: T[] = [];
  for (let i = 0, j = index; i < num; i++) {
    a.push(arr[j++]);
    if (j === arr.length) {
      j = 0;
    }
  }
  return a;
}

/**
 * Remove one exists element from an array