这就是lib"文件夹的用途.

This is what the 'lib' folder is for.

lib 文件夹在自动查找的路径中，所以你可以有

The lib folder is in the automatically looked up path, so you can have

class MyFoo
end

在 lib/my_foo.rb 中，然后只需调用

in lib/my_foo.rb and then just by calling

MyFoo.new

从控制器加载代码，不需要 require 'my_foo'

from a controller the code will be loaded without you needing a require 'my_foo'