arrays - 使用 ruby​​ 从数组创建嵌套哈希

Question

我正在尝试将数组中的数据重新排列为散列格式，但我使用嵌套 if 时搞砸了

示例数据

[
  ["England", "London", "University College London ", "Faculty of Law"], 
  ["England", "London", "University College London ", "Faculty of Engineering"], 
  ["England", "London", "Imperial College London", "Faculty of Medicine"], 
  ["England", "Manchester", "University of Manchester", "Faculty of Engineering"]
]

预期输出

{:name=>"England", 
:level=>1, 
:children=>[{:name=>"London", 
             :level=>2, 
             :children=>[{:name=>"University College London ", 
                          :level=>3, 
                          :children=>[{:name=>"Faculty of Law", 
                                       :level=>4, 
                                       :children=>[]},
                                      {:name=>"Faculty of Engineering", 
                                       :level=>4, :children=>[]}]},
                         {:name=>"Imperial College London", 
                          :level=>3, 
                          :children=>[{:name=>"Faculty of Engineering", 
                                       :level=>4, 
                                      :children=>[]}]
                         }]
           }]
}

希望我能提供清楚的解释

附言。编辑以显示我尝试过的内容首先我制作哈希数组然后做这样的事情我还以为不会这么糊涂呢

result = []
arr.each do |b|
  if result.any? {|r| r[:name] == b[:name]}
    if result.first[:children].any? {|r| r[:name] == b[:children].first[:name]}
      if result.first[:children].any?{|c| c[:children].any? {|r| r[:name] == b[:children].first[:children].first[:name] && c[:name] == b[:children].first[:name] }}
        if result.first[:children].any? {|r| r[:children].any? {|c| c[:children].any?{|k| k[:name] == b[:children].first[:children].first[:children].first[:name] && (c[:name] == b[:children].first[:children].first)}}}

        else
          result.first[:children].any?{|c| c[:children].any? {|r| r[:name] == b[:children].first[:children].first[:name] ; r[:children] << b[:children].first[:children].first[:children].first}}

        end #fourth
      else
        result.first[:children].any? {|r| r[:name] == b[:children].first[:name]; r[:children] << b[:children].first[:children].first}
      end 
    else
      result.any? {|r| r[:name] == b[:name] ; r[:children] << b[:children].first}
    end 
  else result << b 
  end
end

Answer 1

你可以这样递归:

def map_objects(array, level = 1)
  new_obj = []
  array.group_by(&:shift).each do |key, val|
    new_obj << {:name=>key, :level=>level, :children=>map_objects(val, level + 1)} if key
  end
  new_obj
end

对于你的数组，它将像这样返回:

# [
# {:name => "England", :level => 1, :children => [
#     {:name => "London", :level => 2, :children => [
#         {:name => "University College London ", :level => 3, :children => [
#             {:name => "Faculty of Law", :level => 4, :children => []
#             },
#             {:name => "Faculty of Engineering", :level => 4, :children => []
#             }]
#         },
#         {:name => "Imperial College London", :level => 3, :children => [
#             {:name => "Faculty of Medicine", :level => 4, :children => []
#             }]
#         }]
#     },
#     {:name => "Manchester", :level => 2, :children => [
#         {:name => "University of Manchester", :level => 3, :children => [
#             {:name => "Faculty of Engineering", :level => 4, :children => []
#             }]
#         }]
#     }]
# }
# ]