move array position by passing old and new positions.

move-array-position.js

public moveArrayPosition(arr: any[], oldPosition: number, newPosition: number) {
    if (newPosition >= arr.length) {
      let k = newPosition - arr.length + 1;
      while (k--) {
        arr.push(undefined);
      }
    }
    arr.splice(newPosition, 0, arr.splice(oldPosition, 1)[0]);
    return arr;
  }