Function moveItemInArray

src/cdk/drag-drop/drag-utils.ts:15–31

(array: T[], fromIndex: number, toIndex: number)

 * @param toIndex Index to which the item should be moved.
 */
export function moveItemInArray<T = any>(array: T[], fromIndex: number, toIndex: number): void {
  const from = clamp(fromIndex, array.length - 1);
  const to = clamp(toIndex, array.length - 1);

  if (from === to) {
    return;
  }

  const target = array[from];
  const delta = to < from ? -1 : 1;

  for (let i = from; i !== to; i += delta) {
    array[i] = array[i + delta];
  }

  array[to] = target;
}

/**
 * Moves an item from one array to another.