ruby-on-rails - Ruby 散列按多个值分组

Question

我有多个看起来像这样的散列:

[{"name" => "name1", "folder" => "folder1", id => 1 },

{"name" => "name1", "folder" => "folder1", id => 2 },

{"name" => "name1", "folder" => "folder2", id => 3},

{"name" => "name2", "folder" => "folder1", id => 4}]

我的目标是拥有这样的东西:

   {"name1" => 
    [{"folder1" =>
      [{"name" => "name1", "folder" => "folder1", id => 1 },
       {"name" => "name1", "folder" => "folder1", id => 2 }] }
     {"folder2" => 
       [{"name" => "name1", "folder" => "folder2", id => 3}] }]

    {"name2" => 
     [{"folder 1" => 
       [{"name" => "name2", "folder" => "folder1", id => 4}] }] }

我暂时没有找到能给出这种或类似结果的合适解决方案。

编辑:我试过那个和很多其他的，但从来没有找到拥有两层深度哈希的方法 a.group_by{|line| line["name"]}.each_value {|v| v. map {|线|行[“文件夹”]}}

Answer 1

这好像do what you want :

transformed_hash = initial_hash
  .group_by { |x| x['name'] }
  .map { |k, v| [k, v.group_by{ |x| x['folder'] }] }
  .to_h