如何使递归在 Ruby 中正常工作？

Question

我正在尝试用 Ruby 编写 Mastermind 游戏。这是来自 https://www.theodinproject.com/lessons/ruby-mastermind.

的练习

我构建了一个方法 #make-guess 循环 4 次从用户那里获取输入并验证它，即确保输入包含在 #BALL 数组中。

为此，我声明了一个条件，如果输入包含在#BALL 数组中，将其附加到数组#guess，否则，再次调用该函数（递归）。

问题是当不包括输入时，#make-guess 函数循环超过 4 次。 这是我正在处理的代码：

class MasterMind
  BALLS = ['r', 'g', 'o', 'y', 'v', 'm']

  comp_selection = BALLS.sample(4)

  def make_guess
    guess = []
    until guess.length == 4
      puts "Guess the computer's combination from: 'r', 'g', 'o', 'y', 'v', 'm'"
      value = gets.chomp
      if BALLS.include?(value)
        guess.append(value)
      else
        puts 'Selection not in the combination, try again'
        make_guess
      end
    end
    guess
  end

end

master = MasterMind.new
puts master.make_guess

Answer 1

这里不需要递归。 （至少在你使用它的地方）

class MasterMind
  BALLS = ['r', 'g', 'o', 'y', 'v', 'm']

  comp_selection = BALLS.sample(4)

  def make_guess
    guess = []
    until guess.length == 4
      puts "Guess the computer's combination from: 'r', 'g', 'o', 'y', 'v', 'm'"
      value = gets.chomp
      if BALLS.include?(value)
        guess.append(value)
      else
        puts 'Selection not in the combination, try again'
        # Remove this line to fix your problem.
        # make_guess
      end
    end
    guess
  end

end

master = MasterMind.new
puts master.make_guess