ruby - 如何根据一些自定义规则对 ruby​​ 中的哈希进行排序

Question

<分区>

Answer 1

class Hash
  def sort_by_array a; Hash[sort_by{|k, _| a.index(k) || length}] end
end

将适用于第一个示例:

a = ["Is", "Gandalf", "The", "Gray", "Insane"]

{:count=>21, "Is"=>19, "Gandalf"=>1, "Gray"=>0, "Insane"=>1, "The"=>5}.sort_by_array(a)
# => {"Is"=>19, "Gandalf"=>1, "The"=>5, "Gray"=>0, "Insane"=>1, :count=>21}

但是，它不适用于您的第二个示例，因为您期望的第二个示例的结果不仅仅是排序，而且还需要更改 "Gray" 的值:

{:count=>3, "Is"=>11, "Insane"=>22, "Gray"=>0, "Gandalf"=>12, "The"=>2}.sort_by_array(a)
# => {"Is"=>11, "Gandalf"=>12, "The"=>2, "Gray"=>0, "Insane"=>22, :count=>3}

# You wanted
# => {"Is"=>11, "Gandalf"=>12, "The"=>2, "Gray"=>12, "Insane"=>22, :count=>3}

由于不清楚 "Gray" 的值 12 从何而来，因此无法以满足第二个示例的方式回答您的问题。