You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: application_helper.rb
    path of file: ./repos/sample_apps/6_1/ch05/app/helpers
    
    the code of the file until where you have to start completion: module ApplicationHelper

  # ページご
    
  def full_title(page_title = '')
    base_title = "Ruby on Rails Tutorial Sample App"
    if page_title.empty?
      base_title
    else
      page_title + " | " + base_title
    end