红宝石中的康威生命游戏答案

【问题标题】：conways game of life in ruby红宝石中的康威生命游戏
【发布时间】：2023-03-07 21:18:01
【问题描述】：

我正在用 ruby 制作康威生命游戏。这是我的 cell_spec.rb 文件。我在第 10 行遇到了失败/错误：

expect(GameOfLife::Cell.new_dead_cell).to be_dead

我有另一个文件cell.rb，其中定义了类单元格。如何在这个文件中实现自定义谓词数学？

require 'spec_helper'

describe GameOfLife::Cell do 
  def build_neighbours(live_count)
    [GameOfLife::Cell.new_live_cell] * live_count +
       [GameOfLife::Cell.new_dead_cell] * (8 - live_count)
  end
  context "factory" do
    it "can be dead" do
      expect(GameOfLife::Cell.new_dead_cell).to be_dead
    end

    it "can be alive" do
      expect(GameOfLife::Cell.new_live_cell).to be_alive
    end
  end

  context "live cell generation rules" do
    let(:cell) { GameOfLife::Cell.new_live_cell }

    [0, 1].each do |i|
      it "dies when there are #{i} live neighbours" do
        expect(cell.next_generation(build_neighbours(i))).to be_dead
      end
    end

    [2, 3].each do |i|
      it "lives when there are #{i} live neighbours" do
        expect(cell.next_generation(build_neighbours(i))).to be_alive
      end
    end

    (4..8).each do |i|
      it "dead when there are #{i} live neighbours" do
        expect(cell.next_generation(build_neighbours(i))).to be_dead
      end
    end
  end

  context "dead cell generation rules" do
    let(:cell) { GameOfLife::Cell.new_dead_cell }

    (0..2).each do |i|
      it "dies when there are #{i} live neighbours" do
        expect(cell.next_generation(build_neighbours(i))).to be_dead
      end
    end

    [3].each do |i|
      it "lives when there are #{i} live neighbours" do
        expect(cell.next_generation(build_neighbours(i))).to be_alive
      end
    end

    (4..8).each do |i|
      it "dead when there are #{i} live neighbours" do
        expect(cell.next_generation(build_neighbours(i))).to be_dead
      end
    end
  end
end

这是我的具有单元类的 cell.rb 文件。我想知道死亡代码的实现？还活着？方法。请帮帮我

class GameOfLife::Cell
  ALIVE = "alive"
  DEAD = "dead"

 # lost implementation
  def self.new_dead_cell
     return DEAD
  end

  def self.new_live_cell
    return ALIVE
  end

  def dead?

  end

  def alive?

  end

 end

【问题讨论】：

请将完整的错误信息添加到您的问题中。
1) GameOfLife::Cell factory can be dead 失败/错误：expect(GameOfLife::Cell.new_dead_cell).to be_dead 预期死去响应dead? # ./spec/game_of_life/cell_spec .rb:10:in block (3 levels) in <top (required)>' 2) GameOfLife::Cell factory can be alive Failure/Error: expect(GameOfLife::Cell.new_live_cell).to be_alive expected alive to respond to alive?` # ./spec/game_of_life/cell_spec.rb:14:in `block (3 levels) in '
它几乎可以告诉您代码有什么问题。为了使be_dead匹配器工作，你需要在GameOfLife::Cell类中实现dead?方法。
我已经实现死了？方法..但是这个错误是“预期死亡响应死亡？”..这个问题将如何解决def dead？死胡同
new_dead_cell 方法返回了什么？它应该返回实例，所以最后一行应该是self，除非方法中的最后一条语句已经返回了实例。

标签： ruby conways-game-of-life

【解决方案1】：

这是一种明显的方法。您只需创建一个新的 Cell 实例并存储它的状态（如 :dead 或 :alive）。死的？还活着？方法然后简单地检查状态。

 class Cell
  ALIVE = :alive
  DEAD = :dead

  def self.new_dead_cell
     new(DEAD)
  end

  def self.new_live_cell
    new(ALIVE)
  end

  def initialize state
    @state = state
  end
  attr_reader :state

  def dead?
    state == DEAD
  end

  def alive?
    state == ALIVE
  end
end

【讨论】：