code: func (arr Array) Find(path Ref) (Value, error) {
  	if len(path) == 0 {
  		return arr, nil
  	}
  	num, ok := path[0].Value.(Number)
  	if !ok {
  		return nil, fmt.Errorf("find: not found")
  	}
  	i, ok := num.Int()
  	if !ok {
  		return nil, fmt.Errorf("find: not found")
  	}
  	if i < 0 || i >= len(arr) {
  		return nil, fmt.Errorf("find: not found")
  	}
  	return arr[i].Value.Find(path[1:])
  }
docs: // Find returns the value at the index or an out-of-range error.