overriding-1.rb

class MyApp::Interface::NavigationBar
  include ActionView::Helpers::UrlHelper
  
  delegate :url_helpers, to: 'Rails.application.routes'
  
  def initialize(template, current_user)
    @template = template
    @current_user = current_user
  end

  def logo
    # HTML to render a logo goes here.
  end

  def categories
    # In this example, for arguments sake, let us assume that 
    # there exists some complex business logic to render
    # categories based on who the requesting user is. In this
    # case, this is an excellent place to abstract that logic
    # to, allowing our views to worry only about rendering an 
    # instance of MyApp::Interface::NavigationBar.
  end

  def account
    if @current_user.nil?
      link_to :signup, url_helpers.signup_path
    else
      "Welcome #{@current_user.first_name}!"
    end
  end

  def to_s
    @template.render(partial: "navigation_bar", object: self)
  end
end