class Hash
  def self.recursive
    new do |hash, key|
      hash[key] = recursive
    end
  end

  def symbolize_keys
    reduce({}) do |memo, (key, value)|
      memo.merge! key.to_sym => value
    end
  end

  def sort_with_keys
    sort.to_h.tap do |hash|
      hash.each_pair do |key, value|
        hash.merge! key => value.sort_with_keys if value.is_a?(Hash)
      end
    end
  end
end