Include doesn't work inside Rails controller

Question

Consider I have a class located in /lib/foo/bar/baz.rb , defined as following:

module Foo
  module Bar
    class Baz
      def initialize
        self.name = 'Baz'
      end
    end
  end
end

I also have the following controller /controllers/my_controller.rb , defined as following:

class MyController < ApplicationController
  def index
    render json: ::Foo::Bar::Baz.new
  end
end

which outputs JSON {name: "Baz"} as one would expect.

The problem is if I try to include the Foo::Bar module, so I don't have to prepend it to the Baz class name each time I want to use it:

class MyController < ApplicationController
  include ::Foo::Bar

  def index
    render json: ::Baz.new
  end
end

Returns me the following error message: uninitialized constant Baz .

Why???

Answer 1

I think you should try

include ::Foo::Bar
...
render json: Baz.new

Answer 2

::Baz ensures finding the module Baz in the top level namespace, so you should not use this syntax. render json: Baz.new should work.