ruby-on-rails - Ruby 哈希组合

Question

对于一个电子商务应用程序，我试图将选项的散列(每个选项都有一系列选择)转换为代表这些选择组合的散列数组。例如:

# Input:
{ :color => [ "blue", "grey" ],
  :size  => [ "s", "m", "l" ] }

# Output:
[ { :color => "blue", :size => "s" },
  { :color => "blue", :size => "m" },
  { :color => "blue", :size => "m" },
  { :color => "grey", :size => "s" },
  { :color => "grey", :size => "m" },
  { :color => "grey", :size => "m" } ]

Input 内部可能有额外的选项，每个选项的数量不确定，但它只会嵌套 1 层深。任何

Answer 1

上述的变体:

input = { color: [ "blue", "grey" ],
          size:  [ "s", "m", "l" ],
          wt:    [:light, :heavy] }

keys = input.keys
  #=> [:color, :size, :wt]
values = input.values
  #=> [["blue", "grey"], ["s", "m", "l"], [:light, :heavy]]
values.shift.product(*values).map { |v| Hash[keys.zip(v)] }
  #=> [{:color=>"blue", :size=>"s", :wt=>:light},
  #    {:color=>"blue", :size=>"s", :wt=>:heavy},
  #    {:color=>"blue", :size=>"m", :wt=>:light},
  #    {:color=>"blue", :size=>"m", :wt=>:heavy},
  #    {:color=>"blue", :size=>"l", :wt=>:light},
  #    {:color=>"blue", :size=>"l", :wt=>:heavy},
  #    {:color=>"grey", :size=>"s", :wt=>:light},
  #    {:color=>"grey", :size=>"s", :wt=>:heavy},
  #    {:color=>"grey", :size=>"m", :wt=>:light},
  #    {:color=>"grey", :size=>"m", :wt=>:heavy},
  #    {:color=>"grey", :size=>"l", :wt=>:light},
  #    {:color=>"grey", :size=>"l", :wt=>:heavy}]