```ruby
module Derail::Generators
  class LayoutGenerator < Base
    source_root File.expand_path("../../../../templates/layout", __FILE__)

    def install_haml_and_compass
      insert_into_file "Gemfile", "gem 'haml-rails'\n", :after => "# Views helpers\n"

      # Make sure this goes above sass-rails so *_path helpers are overridden
      insert_into_file "Gemfile", "  gem 'compass', :git => 'git://github.com/chriseppstein/compass.git', :branch => 'rails31'\n", :before => /\n  gem 'sass-rails'/

      bundle_install
    end

    def remove_erb
      remove_file "app/views/layouts/application.html.erb"
    end

    def copy_sass_layout
      # Yes, we *do* want to override
      copy_file "application.css.sass", "app/assets/stylesheets/application.css.sass"
    end

    def copy_haml_layouts
      copy_file "application.html.haml", "app/views/layouts/application.html.haml"
      copy_file "canvas.html.haml", "app/views/layouts/canvas.html.haml"
    end
  end
end
```

Add default layout to ApplicationController
user
```ruby
module Derail::Generators
  class LayoutGenerator < Base
    source_root File.expand_path("../../../../templates/layout", __FILE__)

    def install_haml_and_compass
      insert_into_file "Gemfile", "gem 'haml-rails'\n", :after => "# Views helpers\n"

      # Make sure this goes above sass-rails so *_path helpers are overridden
      insert_into_file "Gemfile", "  gem 'compass', :git => 'git://github.com/chriseppstein/compass.git', :branch => 'rails31'\n", :before => /\n  gem 'sass-rails'/

      bundle_install
    end

    def remove_erb
      remove_file "app/views/layouts/application.html.erb"
    end

    def copy_sass_layout
      # Yes, we *do* want to override
      copy_file "application.css.sass", "app/assets/stylesheets/application.css.sass"
    end

    def copy_haml_layouts
      copy_file "application.html.haml", "app/views/layouts/application.html.haml"
      copy_file "canvas.html.haml", "app/views/layouts/canvas.html.haml"
    end

    def insert_layout_into_application_controller
      insert_into_file "app/controllers/application_controller.rb", "\n\n  layout 'canvas'", :before => "\nend"
    end
  end
end
```
assistant