轉換紅寶石結構來YAML

Question

我有紅寶石一個結構，看起來像這樣：

Struct.new("Device", :brand, :model, :port_id) 
@devices = [ 
Struct::Device.new('Apple', 'iphone5', 3), 
Struct::Device.new('Samsung', 'Galaxy S4', 1) 
] 

轉換這個to_yaml給了我這樣的結果：

--- 
- !ruby/struct:Struct::Device 
    brand: Apple 
    model: iphone5 
    port_id: 3 
- !ruby/struct:Struct::Device 
    brand: Samsung 
    model: Galaxy S4 
    port_id: 1 

但是我仍然不知道如何當我需要在我的代碼中使用它時，將我的結構從yaml轉換回來。當我在yaml代碼的頂部添加devices:，然後嘗試從CONFIG ['devices']變量解析回ruby結構 - 我沒有得到任何結果。

任何幫助將不勝感激！

Answer 1

我沒有看到你的問題：

irb(main):001:0> require 'yaml' 
=> true 
irb(main):002:0> Struct.new("Device", :brand, :model, :port_id) 
=> Struct::Device 
irb(main):003:0> devices = [ 
irb(main):004:1* Struct::Device.new('Apple', 'iphone5', 3), 
irb(main):005:1* Struct::Device.new('Samsung', 'Galaxy S4', 1) 
irb(main):006:1> ] 
=> [#<struct Struct::Device brand="Apple", model="iphone5", port_id=3>, #<struct Struct::Device brand="Samsung", model="Galaxy S4", port_id=1>] 
irb(main):007:0> y = devices.to_yaml 
=> "---\n- !ruby/struct:Struct::Device\n brand: Apple\n model: iphone5\n port_id: 3\n- !ruby/struct:Struct::Device\n brand: Samsung\n model: Galaxy S4\n port_id: 1\n" 
irb(main):008:0> obj = YAML::load(y) 
=> [#<struct Struct::Device brand="Apple", model="iphone5", port_id=3>, #<struct Struct::Device brand="Samsung", model="Galaxy S4", port_id=1>] 

你必須確保在YAML::load前Struct.new運行以及前.to_yaml。否則，Ruby不知道如何從文本創建結構。

好吧，正如我所說的，您必須在嘗試加載之前運行Struct定義。另外，您正在試圖建立一個哈希，所以使用YAML語法：

config.yml：

--- 
devices: 
- !ruby/struct:Struct::Device 
    brand: Apple 
    model: iphone5 
    port_id: 3 
- !ruby/struct:Struct::Device 
    brand: Samsung 
    model: Galaxy S4 
    port_id: 1 

而且test.rb：

require 'yaml' 
Struct.new("Device", :brand, :model, :port_id) 
CONFIG = YAML::load_file('./config.yml') unless defined? CONFIG 
devices = CONFIG['devices'] 
puts devices.inspect 

結果：

C:\>ruby test.rb 
[#<struct Struct::Device brand="Apple", model="iphone5", port_id=3>, #<struct Struct::Device brand="Samsung", model="Galaxy S4", port_id=1>]