Ruby on rails Rails4：未定义的方法`尝试失败'；零级：零级

建立一个刽子手游戏并在游戏中获得命名错误，显示，未定义的方法“失败的尝试”为nil:NilClass

显示/Users/neilpatel/Desktop/Rails/hangman/app/views/games/show.html.erb第3行的位置

**零，
“选定字母”=>nil}
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def属性=（散列）
hash.each do |键、值|
发送（“#{key}=”，值）
结束
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def尝试失败
选择字母。选择字母|
！单词。包括？（字母）
}.尺寸
结束
你猜到了吗？
（word.split（“”）-选定的字母。是否为空？
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def完成了吗？
失败的尝试>=最大失败的尝试次数！猜到了吗？
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def选择！（信）
如果完成，则提高游戏错误率？
精选字母我想问题就在这里

def current_game
    @current_game ||= load_current_game
end

如果@current\u game为nil，则将查找未定义的load\u current\u game方法。
即使您有该方法，它也会出于某种原因返回nil。
什么是
当前游戏
？您的
当前游戏
变量是nil.updated application\u controller。rb@Neil
加载当前游戏：在哪里定义？
class Game

  include ActiveModel::AttributeMethods, ActiveModel::Serializers::JSON

  class GameOverError < StandardError; end

  MAX_FAILED_ATTEMPTS = 5 

  attr_accessor :word

  attr_accessor :selected_letters


  def initialize
    @word = 'Hangman'.upcase
    @selected_letters =[]
  end

  def attributes
    {'word' => nil,
      'selected_letters' => nil}
  end

  def attributes=(hash)
    hash.each do |key, value|
      send("#{key}=", value)
    end
  end

  def failed_attempts
    selected_letters.select { |letter|
      !word.include?(letter)
    }.size
  end

  def guessed?
    (word.split('') - selected_letters).empty?
  end

  def finished?
    failed_attempts >= MAX_FAILED_ATTEMPTS || !guessed?
  end

  def select!(letter)
    raise GameOverError if finished?
    selected_letters << letter unless selected_letters.include? letter word.include? letter
  end

end

class GamesController < ApplicationController
  def new
    session[:current_game] = Game.new
    redirect_to game_path
  end

  def show
  end

  def update
    current_game.select! params[:letter]
    update_current_game
  rescue Game::GameOverError
    flash[:alert] = 'This game is Finished....'
  ensure
    redirect_to game_path
  end

  def destroy
    set_current_game nil
    redirect_to root_path
  end
end

class ApplicationController < ActionController::Base
  # Prevent CSRF attacks by raising an exception.
  # For APIs, you may want to use :null_session instead.
  protect_from_forgery with: :exception

  helper_method :current_game

  def current_game
    @current_game ||= load_current_game
  end

  def set_current_game(game)
    @current_game = game
    session[:serialized_current_game] = game.present? ? game.to_json : nil
  end

  def update_current_game
    set_current_game @current_game
  end

def current_game
    @current_game ||= load_current_game
end