Ruby on rails 如何在rails版本3.2.1中注释rails模型

我试着按照一些在线教程在rails中注释我的模型。然而，似乎所有的教程都在谈论过时的注释版本或不正确的安装，这是一个混乱

到目前为止，我尝试了以下方法

1） 在文件中添加了这个

gem 'annotate', '2.4.0'

2） 然后命令：

bundle install

3） 然后我看到注释gem已经安装并显示在命令中

bundle show

bundle exec annotate --position before

4） 最后，为了注释我的模型，我使用了命令

bundle show

bundle exec annotate --position before

此时，我希望对模型进行注释，但得到的是以下错误消息：

/Users/AM/.rvm/gems/ruby-1.9.2-p290/gems/activerecord-3.2.1/lib/active_record/railties/databases.rake:4:in `<top (required)>': undefined method `namespace' for main:Object (NoMethodError)
from /Users/AM/.rvm/gems/ruby-1.9.2-p290/gems/activerecord-3.2.1/lib/active_record/railtie.rb:33:in `load'
from /Users/AM/.rvm/gems/ruby-1.9.2-p290/gems/activerecord-3.2.1/lib/active_record/railtie.rb:33:in `block in <class:Railtie>'
from /Users/AM/.rvm/gems/ruby-1.9.2-p290/gems/railties-3.2.1/lib/rails/railtie.rb:184:in `instance_exec'
from /Users/AM/.rvm/gems/ruby-1.9.2-p290/gems/railties-3.2.1/lib/rails/railtie.rb:184:in `block in load_tasks'
from /Users/AM/.rvm/gems/ruby-1.9.2-p290/gems/railties-3.2.1/lib/rails/railtie.rb:184:in `each'
from /Users/AM/.rvm/gems/ruby-1.9.2-p290/gems/railties-3.2.1/lib/rails/railtie.rb:184:in `load_tasks'
from /Users/AM/.rvm/gems/ruby-1.9.2-p290/gems/railties-3.2.1/lib/rails/engine.rb:423:in `block in load_tasks'
from /Users/AM/.rvm/gems/ruby-1.9.2-p290/gems/railties-3.2.1/lib/rails/application/railties.rb:8:in `each'
from /Users/AM/.rvm/gems/ruby-1.9.2-p290/gems/railties-3.2.1/lib/rails/application/railties.rb:8:in `all'
from /Users/AM/.rvm/gems/ruby-1.9.2-p290/gems/railties-3.2.1/lib/rails/engine.rb:423:in `load_tasks'
from /Users/AM/.rvm/gems/ruby-1.9.2-p290/gems/railties-3.2.1/lib/rails/application.rb:145:in `load_tasks'
from /Users/AM/.rvm/gems/ruby-1.9.2-p290/gems/railties-3.2.1/lib/rails/railtie/configurable.rb:30:in `method_missing'
from Rakefile:7:in `<top (required)>'
from /Users/AM/.rvm/gems/ruby-1.9.2-p290/gems/annotate-2.4.0/lib/annotate.rb:17:in `load'
from /Users/AM/.rvm/gems/ruby-1.9.2-p290/gems/annotate-2.4.0/lib/annotate.rb:17:in `load_tasks'
from /Users/AM/.rvm/gems/ruby-1.9.2-p290/gems/annotate-2.4.0/bin/annotate:66:in `<top (required)>'
from /Users/AM/.rvm/gems/ruby-1.9.2-p290/bin/annotate:19:in `load'
from /Users/AM/.rvm/gems/ruby-1.9.2-p290/bin/annotate:19:in `<main>'

/Users/AM/.rvm/gems/ruby-1.9.2-p290/gems/activerecord-3.2.1/lib/active\u record/railties/databases.rake:4:in`'：main:Object（NoMethodError）的未定义方法“namespace”
from/Users/AM/.rvm/gems/ruby-1.9.2-p290/gems/activerecord-3.2.1/lib/active_record/railtie.rb:33:in'load'
from/Users/AM/.rvm/gems/ruby-1.9.2-p290/gems/activerecord-3.2.1/lib/active\u record/railtie.rb:33:在“块中”
from/Users/AM/.rvm/gems/ruby-1.9.2-p290/gems/railties-3.2.1/lib/rails/railtie.rb:184:in'instance_exec'
from/Users/AM/.rvm/gems/ruby-1.9.2-p290/gems/railties-3.2.1/lib/rails/railtie.rb:184:“加载任务中的块”
from/Users/AM/.rvm/gems/ruby-1.9.2-p290/gems/railties-3.2.1/lib/rails/railtie.rb:184:in'each'
from/Users/AM/.rvm/gems/ruby-1.9.2-p290/gems/railties-3.2.1/lib/rails/railtie.rb:184:在“加载任务”中
from/Users/AM/.rvm/gems/ruby-1.9.2-p290/gems/railties-3.2.1/lib/rails/engine.rb:423:“加载任务中的块”
from/Users/AM/.rvm/gems/ruby-1.9.2-p290/gems/railties-3.2.1/lib/rails/application/railties.rb:8:in'each'
from/Users/AM/.rvm/gems/ruby-1.9.2-p290/gems/railties-3.2.1/lib/rails/application/railties.rb:8:in'all'
from/Users/AM/.rvm/gems/ruby-1.9.2-p290/gems/railties-3.2.1/lib/rails/engine.rb:423:在“加载任务”中
from/Users/AM/.rvm/gems/ruby-1.9.2-p290/gems/railties-3.2.1/lib/rails/application.rb:145:在“加载任务”中
from/Users/AM/.rvm/gems/ruby-1.9.2-p290/gems/railties-3.2.1/lib/rails/railtie/configurable.rb:30:in'method_missing'
来自Rakefile:7:in`'
from/Users/AM/.rvm/gems/ruby-1.9.2-p290/gems/annotate-2.4.0/lib/annotate.rb:17:in'load'
from/Users/AM/.rvm/gems/ruby-1.9.2-p290/gems/annotate-2.4.0/lib/annotate.rb:17:在“加载任务”中
from/Users/AM/.rvm/gems/ruby-1.9.2-p290/gems/annotate-2.4.0/bin/annotate:66:in`'
from/Users/AM/.rvm/gems/ruby-1.9.2-p290/bin/annotate:19:in'load'
from/Users/AM/.rvm/gems/ruby-1.9.2-p290/bin/annotate:19:in`'

所以感觉完全被难住了

关于如何进行有什么想法吗

---

谢谢

尝试使用更新的测试版

gem 'annotate', '2.4.1.beta1'

---

您也可以尝试此gem。

hmm如果不起作用，请在gem文件中列出的任何gem源中获得消息“找不到gem”annotate（=2.4.1.beta）ruby”。在更改gem文件中的版本号后，尝试运行

bundle update annotate

。我发现，有时简单的

捆绑安装
不起作用。这很有效！哇，这东西比我想象的还要复杂！