gistfile1.txt

class CommentsController
  def index
    @comments = if params[:book_id]
      @scope_object = Book.find(params[:book_id])
      @scope_object.comments
    elsif params[:article_id]
      @scope_object = Article.find(params[:article_id])
      @scope_object.comments
    else
      Comment.all
    end
  end
end

gistfile2.txt

Does Rails 3 provide any way to get the scope object without using a plugin like resourcelogic?  Assume we are using nested routes like book_comments_path(@book)

What's the cleanest way to always get the comments scoped when you have a lot of different models that have comments?