如何从(YAML)哈希中递归删除所有具有空值的键? [英] How to recursively remove all keys with empty values from (YAML) hash?

问题描述

我一直在尝试删除 YAML 文件中所有具有空(空白)值或空哈希值的哈希键.

I have been trying to get rid of all hash keys in my YAML file that have empty (blank) values or empty hashes as values.

这篇早期帖子帮助我获得了几乎是对的，但是只要嵌套足够深，递归单行代码就会在我的 YAML 转储中留下空哈希.

This earlier post helped me to get it almost right, but the recursive one-liner leaves my YAML dump with empty hashes whenever there is sufficiently deep nesting.

我非常感谢您对此的任何帮助.谢谢！

I would really appreciate any help on this. Thanks!

proc = Proc.new { |k, v| (v.kind_of?(Hash) && !v.empty? ) ? (v.delete_if(&proc); nil) : v.blank? }

hash = {"x"=>{"m"=>{"n"=>{}}}, 'y' => 'content'}
hash.delete_if(&proc)

实际输出

 {"x"=>{"m"=>{}}, "y"=>"content"} 

期望的输出

{"y"=>"content"}

推荐答案

class Hash
  def delete_blank
    delete_if{|k, v| v.empty? or v.instance_of?(Hash) && v.delete_blank.empty?}
  end
end

p hash.delete_blank
# => {"y"=>"content"}

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