如何使用Rails控制台中的换行符显示实例的值

Question

我开始在rails控制台中使用pry。 当我得到一个Rails模型的实例，该值没有线所示打破这样的：

pry(#<Class:0x1022f60e0>):1> first 
=> #<Article id: 1, name: "What is Music", content: "Music is an art form in which the medium is sound o...", created_at: "2011-08-24 20:35:29", updated_at: "2011-08-24 20:37:22", published_at: "2011-05-13 23:00:00"> 

从http://railscasts.com/episodes/280-pry-with-rails?view=asciicast

有没有办法，以显示与换行符这样的价值观？

Article 
id: 1 
name: "What is Music" 
content: "Music is an art form in which the medium is sound o..." 
created_at: "2011-08-24 20:35:29" 
updated_at: "2011-08-24 20:37:22" 
published_at: "2011-05-13 23:00:00" 

Answer 1

您可以在模型实例上调用.to_yaml！它返回的格式与您要求的格式几乎完全相同。

这里有to_yaml输出的一些例子：

http://yaml4r.sourceforge.net/doc/page/examples.htm

Answer 2

我想，下面的招会为你工作。

arup@linux-wzza:~/Rails/model_prac> rails c 
Loading development environment (Rails 4.1.4) 
2.1.2 :001 > Comment.first 
    Comment Load (0.4ms) SELECT "comments".* FROM "comments" ORDER BY "comments"."id" ASC LIMIT 1 
=> #<Comment id: 1, value_old: "I am a good Boy.", value_new: "I am a bad Boy.", created_at: "2014-08-02 17:36:14", updated_at: "2014-08-02 18:21:42"> 
2.1.2 :002 > y Comment.first 
    Comment Load (0.4ms) SELECT "comments".* FROM "comments" ORDER BY "comments"."id" ASC LIMIT 1 
--- !ruby/object:Comment 
attributes: 
    id: 1 
    value_old: I am a good Boy. 
    value_new: I am a bad Boy. 
    created_at: 2014-08-02 17:36:14.249466000 Z 
    updated_at: 2014-08-02 18:21:42.511522000 Z 
=> nil 
2.1.2 :003 > 

Answer 3

我建议您安装awesome_print。

将它添加到您的Gemfile：

group :development do 
    gem 'awesome_print' 
end 

而且随着bundle install安装。

现在使用ap打印它在控制台：

pry(#<Class:0x1022f60e0>):1> ap first 

#<Article:0x1022f60e0> { 
      :id => 1, 
     :name => "What is Music" 
     :content => "Music is an art form in which the medium is sound o..." 
    :created_at => "2011-08-24 20:35:29" 
    :updated_at => "2011-08-24 20:37:22" 
:published_at => "2011-05-13 23:00:00" 
}