Amazon Q CLI x Phoenix LiveView × 闘魂：最速でTic Tac Toeを爆誕させた話


# はじめに

いよいよはじまりました！
[Qiita Tech Festa](https://qiita.com/tech-festa/2025) :tada::tada::tada: 

https://qiita.com/tech-festa/2025

「[AI・機械学習 Qiita Tech Festa 2025](https://qiita.com/official-events/43ff3363e32f43d7507c)」に参加します。

https://qiita.com/official-events/43ff3363e32f43d7507c

さらに、「[Amazon Q CLI でゲームを作ろう Tシャツキャンペーン](https://aws.amazon.com/jp/blogs/news/build-games-with-amazon-q-cli-and-score-a-t-shirt/)」にも応募します。

https://aws.amazon.com/jp/blogs/news/build-games-with-amazon-q-cli-and-score-a-t-shirt/

あ、ちなみに私にとってのAIは、**アントニオ猪木**さんという世界一強いタッグパートナーです。

# 参考にした記事

スペシャルサンクス記事です。

https://qiita.com/RyoWakabayashi/items/5f1c327ad6b6a699e5d6

@RyoWakabayashi さんの記事により、「[Amazon Q CLI でゲームを作ろう Tシャツキャンペーン](https://aws.amazon.com/jp/blogs/news/build-games-with-amazon-q-cli-and-score-a-t-shirt/)」のことを知り、どんな感じで操作すればよいのかの感触を掴み、「実は Fetch and install dependencies? [Yn] の質問で止まっているので、 Enter キーを押すと進みます」というTipsについても知ることができました。自分ひとりではきっとわからなかったと思います。  

# セットアップ

Step 0: [Elixir](https://elixir-lang.org/)は[asdf](https://asdf-vm.com/)でインストール済です

以降の手順は、「[Amazon Q CLI でゲームを作ろう Tシャツキャンペーン](https://aws.amazon.com/jp/blogs/news/build-games-with-amazon-q-cli-and-score-a-t-shirt/)」内に書いてある**ステップバイステップガイド**に従いました。

![スクリーンショット 2025-06-16 19.45.21.png](https://qiita-image-store.s3.ap-northeast-1.amazonaws.com/0/131808/d8e30bb1-e906-4150-8f8e-61599e664ccc.png)

# Amazon Q CLI への指示という名のお願い

`q` コマンドを実行すると、 Amazon Q CLI とのチャットが開始されますので、以下の指示という名のお願いをしました。

> Phoenix LiveView を使って、ブラウザで遊べる革新的なtic tac toeゲームを作ってください。データベースは不要です。

少しだけ補足と言う名の思い出を書いておきます。

- @RyoWakabayashi さんの記事で知ったTips、`mix phx.new tictactoe --no-ecto`実行中にユーザの入力待ちが発生する件は、**迷わず**`y`を押して歩みを進めました。
    - 「危ぶめば道は無し」です。
- 何か訊ねられたら、`t` （trustの意味） を**迷わず**押しました
    - **Tic Tac Toeだけにマジで`t`押しているだけでできがった感じ（猪木寛至）です！！！**
- 初回起動時にエラーがでて立ち上がりませんでしたが、なんとなく該当しそうなエラー文をはっつけて、修正をお願いしたら、見事に修正をしてくれました
   - 「エラーの原因は、Elixirのリストに対して board[a] のような形式でアクセスしていたことです。Elixirではリストの要素にアクセスするには Enum.at/2 関数を使う必要があります。」とのことでした
- Git操作もお願いしたら、「Amazon Q CLI」さんがやってくれました

![スクリーンショット 2025-06-16 19.06.23.png](https://qiita-image-store.s3.ap-northeast-1.amazonaws.com/0/131808/c9edd5c7-4595-45db-8a1e-177e551ec7be.png)






# Amazon Q CLIとの対話ログ（全文）


隠すほどのこともないので、「Amazon Q CLI」さんとのやりとりを貼っておきます。  
記事が縦に長くなってしまうので折りたたんでおきます。  

<details><summary>Amazon Q CLIさんとの対話</summary>

```bash
$ q
To learn more about MCP safety, see https://docs.aws.amazon.com/amazonq/latest/qdeveloper-ug/command-line-mcp-security.html


    ⢠⣶⣶⣦⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⢀⣤⣶⣿⣿⣿⣶⣦⡀⠀
 ⠀⠀⠀⣾⡿⢻⣿⡆⠀⠀⠀⢀⣄⡄⢀⣠⣤⣤⡀⢀⣠⣤⣤⡀⠀⠀⢀⣠⣤⣤⣤⣄⠀⠀⢀⣤⣤⣤⣤⣤⣤⡀⠀⠀⣀⣤⣤⣤⣀⠀⠀⠀⢠⣤⡀⣀⣤⣤⣄⡀⠀⠀⠀⠀⠀⠀⢠⣿⣿⠋⠀⠀⠀⠙⣿⣿⡆
 ⠀⠀⣼⣿⠇⠀⣿⣿⡄⠀⠀⢸⣿⣿⠛⠉⠻⣿⣿⠛⠉⠛⣿⣿⠀⠀⠘⠛⠉⠉⠻⣿⣧⠀⠈⠛⠛⠛⣻⣿⡿⠀⢀⣾⣿⠛⠉⠻⣿⣷⡀⠀⢸⣿⡟⠛⠉⢻⣿⣷⠀⠀⠀⠀⠀⠀⣼⣿⡏⠀⠀⠀⠀⠀⢸⣿⣿
 ⠀⢰⣿⣿⣤⣤⣼⣿⣷⠀⠀⢸⣿⣿⠀⠀⠀⣿⣿⠀⠀⠀⣿⣿⠀⠀⢀⣴⣶⣶⣶⣿⣿⠀⠀⠀⣠⣾⡿⠋⠀⠀⢸⣿⣿⠀⠀⠀⣿⣿⡇⠀⢸⣿⡇⠀⠀⢸⣿⣿⠀⠀⠀⠀⠀⠀⢹⣿⣇⠀⠀⠀⠀⠀⢸⣿⡿
 ⢀⣿⣿⠋⠉⠉⠉⢻⣿⣇⠀⢸⣿⣿⠀⠀⠀⣿⣿⠀⠀⠀⣿⣿⠀⠀⣿⣿⡀⠀⣠⣿⣿⠀⢀⣴⣿⣋⣀⣀⣀⡀⠘⣿⣿⣄⣀⣠⣿⣿⠃⠀⢸⣿⡇⠀⠀⢸⣿⣿⠀⠀⠀⠀⠀⠀⠈⢿⣿⣦⣀⣀⣀⣴⣿⡿⠃
 ⠚⠛⠋⠀⠀⠀⠀⠘⠛⠛⠀⠘⠛⠛⠀⠀⠀⠛⠛⠀⠀⠀⠛⠛⠀⠀⠙⠻⠿⠟⠋⠛⠛⠀⠘⠛⠛⠛⠛⠛⠛⠃⠀⠈⠛⠿⠿⠿⠛⠁⠀⠀⠘⠛⠃⠀⠀⠘⠛⠛⠀⠀⠀⠀⠀⠀⠀⠀⠙⠛⠿⢿⣿⣿⣋⠀⠀
 ⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠈⠛⠿⢿⡧

╭─────────────────────────────── Did you know? ────────────────────────────────╮
│                                                                              │
│      Set a default model by running q settings chat.defaultModel MODEL.      │
│                          Run /model to learn more.                           │
│                                                                              │
╰──────────────────────────────────────────────────────────────────────────────╯

/help all commands  •  ctrl + j new lines  •  ctrl + s fuzzy search
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
🤖 You are chatting with claude-3.7-sonnet

> Phoenix LiveView を使って、ブラウザで遊べる革新的なtic tac toeゲームを作ってください。データベースは不要です。
Phoenix LiveViewを使ってブラウザで遊べるtic tac toeゲームを作りましょう。データ
ベースは使わずに、LiveViewの状態管理だけで実装します。

まず、新しいPhoenixプロジェクトを作成しましょう。


🛠️  Using tool: execute_bash
 ⋮ 
 ● I will run the following shell command: 
mix phx.new tictactoe --no-ecto
 ⋮ 
 ↳ Purpose: 新しいPhoenixプロジェクトを作成（データベースなし）


Allow this action? Use 't' to trust (always allow) this tool for the session. [y/n/t]:

> t
* creating tictactoe/lib/tictactoe/application.ex
* creating tictactoe/lib/tictactoe.ex
* creating tictactoe/lib/tictactoe_web/controllers/error_json.ex
* creating tictactoe/lib/tictactoe_web/endpoint.ex
* creating tictactoe/lib/tictactoe_web/router.ex
* creating tictactoe/lib/tictactoe_web/telemetry.ex
* creating tictactoe/lib/tictactoe_web.ex
* creating tictactoe/mix.exs
* creating tictactoe/README.md
* creating tictactoe/.formatter.exs
* creating tictactoe/.gitignore
* creating tictactoe/test/support/conn_case.ex
* creating tictactoe/test/test_helper.exs
* creating tictactoe/test/tictactoe_web/controllers/error_json_test.exs
* creating tictactoe/lib/tictactoe_web/controllers/error_html.ex
* creating tictactoe/test/tictactoe_web/controllers/error_html_test.exs
* creating tictactoe/lib/tictactoe_web/components/core_components.ex
* creating tictactoe/lib/tictactoe_web/controllers/page_controller.ex
* creating tictactoe/lib/tictactoe_web/controllers/page_html.ex
* creating tictactoe/lib/tictactoe_web/controllers/page_html/home.html.heex
* creating tictactoe/test/tictactoe_web/controllers/page_controller_test.exs
* creating tictactoe/lib/tictactoe_web/components/layouts/root.html.heex
* creating tictactoe/lib/tictactoe_web/components/layouts/app.html.heex
* creating tictactoe/lib/tictactoe_web/components/layouts.ex
* creating tictactoe/priv/static/images/logo.svg
* creating tictactoe/lib/tictactoe/mailer.ex
* creating tictactoe/lib/tictactoe_web/gettext.ex
* creating tictactoe/priv/gettext/en/LC_MESSAGES/errors.po
* creating tictactoe/priv/gettext/errors.pot
* creating tictactoe/priv/static/robots.txt
* creating tictactoe/priv/static/favicon.ico
* creating tictactoe/assets/js/app.js
* creating tictactoe/assets/vendor/topbar.js
* creating tictactoe/assets/css/app.css
* creating tictactoe/assets/tailwind.config.js

y
Fetch and install dependencies? [Yn] * running mix deps.get
* running mix assets.setup
* running mix deps.compile

We are almost there! The following steps are missing:

    $ cd tictactoe

Start your Phoenix app with:

    $ mix phx.server

You can also run your app inside IEx (Interactive Elixir) as:

    $ iex -S mix phx.server


 ⋮ 
 ● Completed in 24.640s
プロジェクトが作成できました。次に、tic tac toeゲーム用のLiveViewモジュールを作
成しましょう。


🛠️  Using tool: execute_bash (trusted)
 ⋮ 
 ● I will run the following shell command: cd tictactoe
 ⋮ 
 ↳ Purpose: プロジェクトディレクトリに移動


 ⋮ 
 ● Completed in 0.5s



🛠️  Using tool: fs_write
 ⋮ 
 ● Path: /Users/yamauchi/Documents/13_Elixir/games/tictactoe/lib/tictactoe_web/live/game_live.ex

+      1: defmodule TictactoeWeb.GameLive do
+      2:   use TictactoeWeb, :live_view
+      3: 
+      4:   @impl true
+      5:   def mount(_params, _session, socket) do
+      6:     {:ok, assign(socket, 
+      7:       board: List.duplicate(nil, 9),
+      8:       current_player: "X",
+      9:       game_over: false,
+     10:       winner: nil,
+     11:       game_state: "playing"
+     12:     )}
+     13:   end
+     14: 
+     15:   @impl true
+     16:   def render(assigns) do
+     17:     ~H"""
+     18:     <div class="max-w-md mx-auto mt-10 p-6 bg-white rounded-lg shadow-lg">
+     19:       <h1 class="text-3xl font-bold text-center mb-6">Tic Tac Toe</h1>
+     20:       
+     21:       <div class="mb-4 text-center">
+     22:         <%= if @game_over do %>
+     23:           <%= if @winner do %>
+     24:             <div class="text-2xl font-bold text-green-600">Player <%= @winner %> wins!</div>
+     25:           <% else %>
+     26:             <div class="text-2xl font-bold text-blue-600">It's a draw!</div>
+     27:           <% end %>
+     28:         <% else %>
+     29:           <div class="text-xl">Current player: <span class="font-bold"><%= @current_player %></span></div>
+     30:         <% end %>
+     31:       </div>
+     32:       
+     33:       <div class="grid grid-cols-3 gap-2 mb-6">
+     34:         <%= for {cell, index} <- Enum.with_index(@board) do %>
+     35:           <button 
+     36:             phx-click="mark" 
+     37:             phx-value-index={index} 
+     38:             disabled={cell != nil || @game_over}
+     39:             class={"w-24 h-24 text-4xl font-bold flex items-center justify-center 
+     40:                    #{cell_color(cell)} 
+     41:                    #{if cell, do: "", else: "hover:bg-gray-100"} 
+     42:                    border-2 border-gray-300 rounded-md"}>
+     43:             <%= cell %>
+     44:           </button>
+     45:         <% end %>
+     46:       </div>
+     47:       
+     48:       <div class="text-center">
+     49:         <button phx-click="restart" class="px-4 py-2 bg-blue-500 text-white rounded hover:bg-blue-600">
+     50:           Restart Game
+     51:         </button>
+     52:       </div>
+     53:     </div>
+     54:     """
+     55:   end
+     56: 
+     57:   @impl true
+     58:   def handle_event("mark", %{"index" => index}, socket) do
+     59:     index = String.to_integer(index)
+     60:     
+     61:     if can_mark?(socket.assigns.board, index) do
+     62:       board = List.replace_at(socket.assigns.board, index, socket.assigns.current_player)
+     63:       
+     64:       {game_over, winner} = check_winner(board)
+     65:       
+     66:       next_player = if socket.assigns.current_player == "X", do: "O", else: "X"
+     67:       
+     68:       game_state = cond do
+     69:         winner -> "won"
+     70:         Enum.all?(board, &(&1 != nil)) -> "draw"
+     71:         true -> "playing"
+     72:       end
+     73:       
+     74:       {:noreply, assign(socket, 
+     75:         board: board, 
+     76:         current_player: next_player,
+     77:         game_over: game_over,
+     78:         winner: winner,
+     79:         game_state: game_state
+     80:       )}
+     81:     else
+     82:       {:noreply, socket}
+     83:     end
+     84:   end
+     85: 
+     86:   @impl true
+     87:   def handle_event("restart", _params, socket) do
+     88:     {:noreply, assign(socket, 
+     89:       board: List.duplicate(nil, 9),
+     90:       current_player: "X",
+     91:       game_over: false,
+     92:       winner: nil,
+     93:       game_state: "playing"
+     94:     )}
+     95:   end
+     96: 
+     97:   defp can_mark?(board, index) do
+     98:     Enum.at(board, index) == nil
+     99:   end
+    100: 
+    101:   defp check_winner(board) do
+    102:     winning_combinations = [
+    103:       # Rows
+    104:       [0, 1, 2], [3, 4, 5], [6, 7, 8],
+    105:       # Columns
+    106:       [0, 3, 6], [1, 4, 7], [2, 5, 8],
+    107:       # Diagonals
+    108:       [0, 4, 8], [2, 4, 6]
+    109:     ]
+    110: 
+    111:     winner = Enum.find_value(winning_combinations, fn [a, b, c] ->
+    112:       if board[a] && board[a] == board[b] && board[a] == board[c] do
+    113:         board[a]
+    114:       else
+    115:         nil
+    116:       end
+    117:     end)
+    118: 
+    119:     game_over = winner != nil || Enum.all?(board, &(&1 != nil))
+    120:     
+    121:     {game_over, winner}
+    122:   end
+    123: 
+    124:   defp cell_color(nil), do: "bg-white"
+    125:   defp cell_color("X"), do: "bg-red-100 text-red-600"
+    126:   defp cell_color("O"), do: "bg-blue-100 text-blue-600"
+    127: end


Allow this action? Use 't' to trust (always allow) this tool for the session. [y/n/t]:

> 起動してください。
プロジェクトを起動するために、まずはTic Tac Toeゲームの実装を完成させましょう。


🛠️  Using tool: fs_write
 ⋮ 
 ● Path: /Users/yamauchi/Documents/13_Elixir/games/tictactoe/lib/tictactoe_web/live/game_live.ex

+      1: defmodule TictactoeWeb.GameLive do
+      2:   use TictactoeWeb, :live_view
+      3: 
+      4:   @impl true
+      5:   def mount(_params, _session, socket) do
+      6:     {:ok, assign(socket, 
+      7:       board: List.duplicate(nil, 9),
+      8:       current_player: "X",
+      9:       game_over: false,
+     10:       winner: nil,
+     11:       game_state: "playing"
+     12:     )}
+     13:   end
+     14: 
+     15:   @impl true
+     16:   def render(assigns) do
+     17:     ~H"""
+     18:     <div class="max-w-md mx-auto mt-10 p-6 bg-white rounded-lg shadow-lg">
+     19:       <h1 class="text-3xl font-bold text-center mb-6">Tic Tac Toe</h1>
+     20:       
+     21:       <div class="mb-4 text-center">
+     22:         <%= if @game_over do %>
+     23:           <%= if @winner do %>
+     24:             <div class="text-2xl font-bold text-green-600">Player <%= @winner %> wins!</div>
+     25:           <% else %>
+     26:             <div class="text-2xl font-bold text-blue-600">It's a draw!</div>
+     27:           <% end %>
+     28:         <% else %>
+     29:           <div class="text-xl">Current player: <span class="font-bold"><%= @current_player %></span></div>
+     30:         <% end %>
+     31:       </div>
+     32:       
+     33:       <div class="grid grid-cols-3 gap-2 mb-6">
+     34:         <%= for {cell, index} <- Enum.with_index(@board) do %>
+     35:           <button 
+     36:             phx-click="mark" 
+     37:             phx-value-index={index} 
+     38:             disabled={cell != nil || @game_over}
+     39:             class={"w-24 h-24 text-4xl font-bold flex items-center justify-center 
+     40:                    #{cell_color(cell)} 
+     41:                    #{if cell, do: "", else: "hover:bg-gray-100"} 
+     42:                    border-2 border-gray-300 rounded-md"}>
+     43:             <%= cell %>
+     44:           </button>
+     45:         <% end %>
+     46:       </div>
+     47:       
+     48:       <div class="text-center">
+     49:         <button phx-click="restart" class="px-4 py-2 bg-blue-500 text-white rounded hover:bg-blue-600">
+     50:           Restart Game
+     51:         </button>
+     52:       </div>
+     53:     </div>
+     54:     """
+     55:   end
+     56: 
+     57:   @impl true
+     58:   def handle_event("mark", %{"index" => index}, socket) do
+     59:     index = String.to_integer(index)
+     60:     
+     61:     if can_mark?(socket.assigns.board, index) do
+     62:       board = List.replace_at(socket.assigns.board, index, socket.assigns.current_player)
+     63:       
+     64:       {game_over, winner} = check_winner(board)
+     65:       
+     66:       next_player = if socket.assigns.current_player == "X", do: "O", else: "X"
+     67:       
+     68:       game_state = cond do
+     69:         winner -> "won"
+     70:         Enum.all?(board, &(&1 != nil)) -> "draw"
+     71:         true -> "playing"
+     72:       end
+     73:       
+     74:       {:noreply, assign(socket, 
+     75:         board: board, 
+     76:         current_player: next_player,
+     77:         game_over: game_over,
+     78:         winner: winner,
+     79:         game_state: game_state
+     80:       )}
+     81:     else
+     82:       {:noreply, socket}
+     83:     end
+     84:   end
+     85: 
+     86:   @impl true
+     87:   def handle_event("restart", _params, socket) do
+     88:     {:noreply, assign(socket, 
+     89:       board: List.duplicate(nil, 9),
+     90:       current_player: "X",
+     91:       game_over: false,
+     92:       winner: nil,
+     93:       game_state: "playing"
+     94:     )}
+     95:   end
+     96: 
+     97:   defp can_mark?(board, index) do
+     98:     Enum.at(board, index) == nil
+     99:   end
+    100: 
+    101:   defp check_winner(board) do
+    102:     winning_combinations = [
+    103:       # Rows
+    104:       [0, 1, 2], [3, 4, 5], [6, 7, 8],
+    105:       # Columns
+    106:       [0, 3, 6], [1, 4, 7], [2, 5, 8],
+    107:       # Diagonals
+    108:       [0, 4, 8], [2, 4, 6]
+    109:     ]
+    110: 
+    111:     winner = Enum.find_value(winning_combinations, fn [a, b, c] ->
+    112:       if board[a] && board[a] == board[b] && board[a] == board[c] do
+    113:         board[a]
+    114:       else
+    115:         nil
+    116:       end
+    117:     end)
+    118: 
+    119:     game_over = winner != nil || Enum.all?(board, &(&1 != nil))
+    120:     
+    121:     {game_over, winner}
+    122:   end
+    123: 
+    124:   defp cell_color(nil), do: "bg-white"
+    125:   defp cell_color("X"), do: "bg-red-100 text-red-600"
+    126:   defp cell_color("O"), do: "bg-blue-100 text-blue-600"
+    127: end


Allow this action? Use 't' to trust (always allow) this tool for the session. [y/n/t]:

> t
Creating: /Users/yamauchi/Documents/13_Elixir/games/tictactoe/lib/tictactoe_web/live/game_live.ex

 ⋮ 
 ● Completed in 0.2s



🛠️  Using tool: fs_write (trusted)
 ⋮ 
 ● Path: tictactoe/lib/tictactoe_web/router.ex

  17, 17:   scope "/", TictactoeWeb do
  18, 18:     pipe_through :browser
  19, 19: 
  20, 20:     get "/", PageController, :home
+     21:     live "/game", GameLive
  21, 22:   end

Updating: tictactoe/lib/tictactoe_web/router.ex

 ⋮ 
 ● Completed in 0.0s



🛠️  Using tool: execute_bash (trusted)
 ⋮ 
 ● I will run the following shell command: 
cd tictactoe && mix phx.server
 ⋮ 
 ↳ Purpose: プロジェクトを起動

Compiling 15 files (.ex)
Generated tictactoe app
[info] Running TictactoeWeb.Endpoint with Bandit 1.7.0 at 127.0.0.1:4000 (http)
[info] Access TictactoeWeb.Endpoint at http://localhost:4000
[watch] build finished, watching for changes...

Rebuilding...

Done in 143ms.
[info] GET /
[debug] Processing with TictactoeWeb.PageController.home/2
  Parameters: %{}
  Pipelines: [:browser]
[info] Sent 200 in 25ms
[info] GET /game
[debug] Processing with TictactoeWeb.GameLive.nil/2
  Parameters: %{}
  Pipelines: [:browser]
[info] Sent 200 in 17ms
[info] CONNECTED TO Phoenix.LiveView.Socket in 13µs
  Transport: :websocket
  Serializer: Phoenix.Socket.V2.JSONSerializer
  Parameters: %{"_csrf_token" => "Tzx9WycJGxcUFxsLOBkpNxoEfB8wADAM7T6iKp6ayxRYWAHohi12tZeD", "_live_referer" => "undefined", "_mount_attempts" => "0", "_mounts" => "0", "_track_static" => %{"0" => "http://localhost:4000/assets/app.css", "1" => "http://localhost:4000/assets/app.js"}, "vsn" => "2.0.0"}
[debug] MOUNT TictactoeWeb.GameLive
  Parameters: %{}
  Session: %{"_csrf_token" => "xhK2ly-vmoIRoXaXrmM-DZUH"}
[debug] Replied in 116µs
[debug] HANDLE EVENT "mark" in TictactoeWeb.GameLive
  Parameters: %{"index" => "1", "value" => ""}
[error] GenServer #PID<0.766.0> terminating
** (ArgumentError) the Access module does not support accessing lists by index, got: 0

Accessing a list by index is typically discouraged in Elixir, instead we prefer to use the Enum module to manipulate lists as a whole. If you really must access a list element by index, you can use Enum.at/2 or the functions in the List module
    (elixir 1.18.3) lib/access.ex:347: Access.get/3
    (tictactoe 0.1.0) lib/tictactoe_web/live/game_live.ex:112: anonymous fn/2 in TictactoeWeb.GameLive.check_winner/1
    (elixir 1.18.3) lib/enum.ex:4432: Enum.find_value_list/3
    (tictactoe 0.1.0) lib/tictactoe_web/live/game_live.ex:111: TictactoeWeb.GameLive.check_winner/1
    (tictactoe 0.1.0) lib/tictactoe_web/live/game_live.ex:64: TictactoeWeb.GameLive.handle_event/3
    (phoenix_live_view 1.0.17) lib/phoenix_live_view/channel.ex:509: anonymous fn/3 in Phoenix.LiveView.Channel.view_handle_event/3
    (telemetry 1.3.0) /Users/yamauchi/Documents/13_Elixir/games/tictactoe/deps/telemetry/src/telemetry.erl:324: :telemetry.span/3
    (phoenix_live_view 1.0.17) lib/phoenix_live_view/channel.ex:260: Phoenix.LiveView.Channel.handle_info/2
    (stdlib 6.2.2) gen_server.erl:2345: :gen_server.try_handle_info/3
    (stdlib 6.2.2) gen_server.erl:2433: :gen_server.handle_msg/6
    (stdlib 6.2.2) proc_lib.erl:329: :proc_lib.init_p_do_apply/3
Last message: %Phoenix.Socket.Message{topic: "lv:phx-GEl9gRshWKOdcQFm", event: "event", payload: %{"event" => "mark", "type" => "click", "value" => %{"index" => "1", "value" => ""}}, ref: "12", join_ref: "4"}
State: %{socket: #Phoenix.LiveView.Socket<id: "phx-GEl9gRshWKOdcQFm", endpoint: TictactoeWeb.Endpoint, view: TictactoeWeb.GameLive, parent_pid: nil, root_pid: #PID<0.766.0>, router: TictactoeWeb.Router, assigns: %{flash: %{}, __changed__: %{}, board: [nil, nil, nil, nil, nil, nil, nil, nil, nil], current_player: "X", game_over: false, winner: nil, game_state: "playing", live_action: nil}, transport_pid: #PID<0.758.0>, sticky?: false, ...>, components: {%{}, %{}, 1}, topic: "lv:phx-GEl9gRshWKOdcQFm", serializer: Phoenix.Socket.V2.JSONSerializer, join_ref: "4", redirect_count: 0, upload_names: %{}, upload_pids: %{}}
[debug] MOUNT TictactoeWeb.GameLive
  Parameters: %{}
  Session: %{"_csrf_token" => "xhK2ly-vmoIRoXaXrmM-DZUH"}
[debug] Replied in 193µs
[debug] HANDLE EVENT "mark" in TictactoeWeb.GameLive
  Parameters: %{"index" => "1", "value" => ""}
[error] GenServer #PID<0.767.0> terminating
** (ArgumentError) the Access module does not support accessing lists by index, got: 0

Accessing a list by index is typically discouraged in Elixir, instead we prefer to use the Enum module to manipulate lists as a whole. If you really must access a list element by index, you can use Enum.at/2 or the functions in the List module
    (elixir 1.18.3) lib/access.ex:347: Access.get/3
    (tictactoe 0.1.0) lib/tictactoe_web/live/game_live.ex:112: anonymous fn/2 in TictactoeWeb.GameLive.check_winner/1
    (elixir 1.18.3) lib/enum.ex:4432: Enum.find_value_list/3
    (tictactoe 0.1.0) lib/tictactoe_web/live/game_live.ex:111: TictactoeWeb.GameLive.check_winner/1
    (tictactoe 0.1.0) lib/tictactoe_web/live/game_live.ex:64: TictactoeWeb.GameLive.handle_event/3
    (phoenix_live_view 1.0.17) lib/phoenix_live_view/channel.ex:509: anonymous fn/3 in Phoenix.LiveView.Channel.view_handle_event/3
    (telemetry 1.3.0) /Users/yamauchi/Documents/13_Elixir/games/tictactoe/deps/telemetry/src/telemetry.erl:324: :telemetry.span/3
    (phoenix_live_view 1.0.17) lib/phoenix_live_view/channel.ex:260: Phoenix.LiveView.Channel.handle_info/2
    (stdlib 6.2.2) gen_server.erl:2345: :gen_server.try_handle_info/3
    (stdlib 6.2.2) gen_server.erl:2433: :gen_server.handle_msg/6
    (stdlib 6.2.2) proc_lib.erl:329: :proc_lib.init_p_do_apply/3
Last message: %Phoenix.Socket.Message{topic: "lv:phx-GEl9gRshWKOdcQFm", event: "event", payload: %{"event" => "mark", "type" => "click", "value" => %{"index" => "1", "value" => ""}}, ref: "14", join_ref: "13"}
State: %{socket: #Phoenix.LiveView.Socket<id: "phx-GEl9gRshWKOdcQFm", endpoint: TictactoeWeb.Endpoint, view: TictactoeWeb.GameLive, parent_pid: nil, root_pid: #PID<0.767.0>, router: TictactoeWeb.Router, assigns: %{flash: %{}, __changed__: %{}, board: [nil, nil, nil, nil, nil, nil, nil, nil, nil], current_player: "X", game_over: false, winner: nil, game_state: "playing", live_action: nil}, transport_pid: #PID<0.758.0>, sticky?: false, ...>, components: {%{}, %{}, 1}, topic: "lv:phx-GEl9gRshWKOdcQFm", serializer: Phoenix.Socket.V2.JSONSerializer, join_ref: "13", redirect_count: 0, upload_names: %{}, upload_pids: %{}}
[debug] MOUNT TictactoeWeb.GameLive
  Parameters: %{}
  Session: %{"_csrf_token" => "xhK2ly-vmoIRoXaXrmM-DZUH"}
[debug] Replied in 334µs
[debug] HANDLE EVENT "mark" in TictactoeWeb.GameLive
  Parameters: %{"index" => "3", "value" => ""}
[error] GenServer #PID<0.768.0> terminating
** (ArgumentError) the Access module does not support accessing lists by index, got: 0

Accessing a list by index is typically discouraged in Elixir, instead we prefer to use the Enum module to manipulate lists as a whole. If you really must access a list element by index, you can use Enum.at/2 or the functions in the List module
    (elixir 1.18.3) lib/access.ex:347: Access.get/3
    (tictactoe 0.1.0) lib/tictactoe_web/live/game_live.ex:112: anonymous fn/2 in TictactoeWeb.GameLive.check_winner/1
    (elixir 1.18.3) lib/enum.ex:4432: Enum.find_value_list/3
    (tictactoe 0.1.0) lib/tictactoe_web/live/game_live.ex:111: TictactoeWeb.GameLive.check_winner/1
    (tictactoe 0.1.0) lib/tictactoe_web/live/game_live.ex:64: TictactoeWeb.GameLive.handle_event/3
    (phoenix_live_view 1.0.17) lib/phoenix_live_view/channel.ex:509: anonymous fn/3 in Phoenix.LiveView.Channel.view_handle_event/3
    (telemetry 1.3.0) /Users/yamauchi/Documents/13_Elixir/games/tictactoe/deps/telemetry/src/telemetry.erl:324: :telemetry.span/3
    (phoenix_live_view 1.0.17) lib/phoenix_live_view/channel.ex:260: Phoenix.LiveView.Channel.handle_info/2
    (stdlib 6.2.2) gen_server.erl:2345: :gen_server.try_handle_info/3
    (stdlib 6.2.2) gen_server.erl:2433: :gen_server.handle_msg/6
    (stdlib 6.2.2) proc_lib.erl:329: :proc_lib.init_p_do_apply/3
Last message: %Phoenix.Socket.Message{topic: "lv:phx-GEl9gRshWKOdcQFm", event: "event", payload: %{"event" => "mark", "type" => "click", "value" => %{"index" => "3", "value" => ""}}, ref: "16", join_ref: "15"}
State: %{socket: #Phoenix.LiveView.Socket<id: "phx-GEl9gRshWKOdcQFm", endpoint: TictactoeWeb.Endpoint, view: TictactoeWeb.GameLive, parent_pid: nil, root_pid: #PID<0.768.0>, router: TictactoeWeb.Router, assigns: %{flash: %{}, __changed__: %{}, board: [nil, nil, nil, nil, nil, nil, nil, nil, nil], current_player: "X", game_over: false, winner: nil, game_state: "playing", live_action: nil}, transport_pid: #PID<0.758.0>, sticky?: false, ...>, components: {%{}, %{}, 1}, topic: "lv:phx-GEl9gRshWKOdcQFm", serializer: Phoenix.Socket.V2.JSONSerializer, join_ref: "15", redirect_count: 0, upload_names: %{}, upload_pids: %{}}
[debug] MOUNT TictactoeWeb.GameLive
  Parameters: %{}
  Session: %{"_csrf_token" => "xhK2ly-vmoIRoXaXrmM-DZUH"}
[debug] Replied in 321µs
[debug] HANDLE EVENT "mark" in TictactoeWeb.GameLive
  Parameters: %{"index" => "4", "value" => ""}
[error] GenServer #PID<0.769.0> terminating
** (ArgumentError) the Access module does not support accessing lists by index, got: 0

Accessing a list by index is typically discouraged in Elixir, instead we prefer to use the Enum module to manipulate lists as a whole. If you really must access a list element by index, you can use Enum.at/2 or the functions in the List module
    (elixir 1.18.3) lib/access.ex:347: Access.get/3
    (tictactoe 0.1.0) lib/tictactoe_web/live/game_live.ex:112: anonymous fn/2 in TictactoeWeb.GameLive.check_winner/1
    (elixir 1.18.3) lib/enum.ex:4432: Enum.find_value_list/3
    (tictactoe 0.1.0) lib/tictactoe_web/live/game_live.ex:111: TictactoeWeb.GameLive.check_winner/1
    (tictactoe 0.1.0) lib/tictactoe_web/live/game_live.ex:64: TictactoeWeb.GameLive.handle_event/3
    (phoenix_live_view 1.0.17) lib/phoenix_live_view/channel.ex:509: anonymous fn/3 in Phoenix.LiveView.Channel.view_handle_event/3
    (telemetry 1.3.0) /Users/yamauchi/Documents/13_Elixir/games/tictactoe/deps/telemetry/src/telemetry.erl:324: :telemetry.span/3
    (phoenix_live_view 1.0.17) lib/phoenix_live_view/channel.ex:260: Phoenix.LiveView.Channel.handle_info/2
    (stdlib 6.2.2) gen_server.erl:2345: :gen_server.try_handle_info/3
    (stdlib 6.2.2) gen_server.erl:2433: :gen_server.handle_msg/6
    (stdlib 6.2.2) proc_lib.erl:329: :proc_lib.init_p_do_apply/3
Last message: %Phoenix.Socket.Message{topic: "lv:phx-GEl9gRshWKOdcQFm", event: "event", payload: %{"event" => "mark", "type" => "click", "value" => %{"index" => "4", "value" => ""}}, ref: "18", join_ref: "17"}
State: %{socket: #Phoenix.LiveView.Socket<id: "phx-GEl9gRshWKOdcQFm", endpoint: TictactoeWeb.Endpoint, view: TictactoeWeb.GameLive, parent_pid: nil, root_pid: #PID<0.769.0>, router: TictactoeWeb.Router, assigns: %{flash: %{}, __changed__: %{}, board: [nil, nil, nil, nil, nil, nil, nil, nil, nil], current_player: "X", game_over: false, winner: nil, game_state: "playing", live_action: nil}, transport_pid: #PID<0.758.0>, sticky?: false, ...>, components: {%{}, %{}, 1}, topic: "lv:phx-GEl9gRshWKOdcQFm", serializer: Phoenix.Socket.V2.JSONSerializer, join_ref: "17", redirect_count: 0, upload_names: %{}, upload_pids: %{}}
[debug] MOUNT TictactoeWeb.GameLive
  Parameters: %{}
  Session: %{"_csrf_token" => "xhK2ly-vmoIRoXaXrmM-DZUH"}
[debug] Replied in 245µs
[debug] HANDLE EVENT "mark" in TictactoeWeb.GameLive
  Parameters: %{"index" => "7", "value" => ""}
[error] GenServer #PID<0.770.0> terminating
** (ArgumentError) the Access module does not support accessing lists by index, got: 0

Accessing a list by index is typically discouraged in Elixir, instead we prefer to use the Enum module to manipulate lists as a whole. If you really must access a list element by index, you can use Enum.at/2 or the functions in the List module
    (elixir 1.18.3) lib/access.ex:347: Access.get/3
    (tictactoe 0.1.0) lib/tictactoe_web/live/game_live.ex:112: anonymous fn/2 in TictactoeWeb.GameLive.check_winner/1
    (elixir 1.18.3) lib/enum.ex:4432: Enum.find_value_list/3
    (tictactoe 0.1.0) lib/tictactoe_web/live/game_live.ex:111: TictactoeWeb.GameLive.check_winner/1
    (tictactoe 0.1.0) lib/tictactoe_web/live/game_live.ex:64: TictactoeWeb.GameLive.handle_event/3
    (phoenix_live_view 1.0.17) lib/phoenix_live_view/channel.ex:509: anonymous fn/3 in Phoenix.LiveView.Channel.view_handle_event/3
    (telemetry 1.3.0) /Users/yamauchi/Documents/13_Elixir/games/tictactoe/deps/telemetry/src/telemetry.erl:324: :telemetry.span/3
    (phoenix_live_view 1.0.17) lib/phoenix_live_view/channel.ex:260: Phoenix.LiveView.Channel.handle_info/2
    (stdlib 6.2.2) gen_server.erl:2345: :gen_server.try_handle_info/3
    (stdlib 6.2.2) gen_server.erl:2433: :gen_server.handle_msg/6
    (stdlib 6.2.2) proc_lib.erl:329: :proc_lib.init_p_do_apply/3
Last message: %Phoenix.Socket.Message{topic: "lv:phx-GEl9gRshWKOdcQFm", event: "event", payload: %{"event" => "mark", "type" => "click", "value" => %{"index" => "7", "value" => ""}}, ref: "20", join_ref: "19"}
State: %{socket: #Phoenix.LiveView.Socket<id: "phx-GEl9gRshWKOdcQFm", endpoint: TictactoeWeb.Endpoint, view: TictactoeWeb.GameLive, parent_pid: nil, root_pid: #PID<0.770.0>, router: TictactoeWeb.Router, assigns: %{flash: %{}, __changed__: %{}, board: [nil, nil, nil, nil, nil, nil, nil, nil, nil], current_player: "X", game_over: false, winner: nil, game_state: "playing", live_action: nil}, transport_pid: #PID<0.758.0>, sticky?: false, ...>, components: {%{}, %{}, 1}, topic: "lv:phx-GEl9gRshWKOdcQFm", serializer: Phoenix.Socket.V2.JSONSerializer, join_ref: "19", redirect_count: 0, upload_names: %{}, upload_pids: %{}}
[debug] MOUNT TictactoeWeb.GameLive
  Parameters: %{}
  Session: %{"_csrf_token" => "xhK2ly-vmoIRoXaXrmM-DZUH"}
[debug] Replied in 206µs
[debug] HANDLE EVENT "mark" in TictactoeWeb.GameLive
  Parameters: %{"index" => "1", "value" => ""}
[error] GenServer #PID<0.771.0> terminating
** (ArgumentError) the Access module does not support accessing lists by index, got: 0

Accessing a list by index is typically discouraged in Elixir, instead we prefer to use the Enum module to manipulate lists as a whole. If you really must access a list element by index, you can use Enum.at/2 or the functions in the List module
    (elixir 1.18.3) lib/access.ex:347: Access.get/3
    (tictactoe 0.1.0) lib/tictactoe_web/live/game_live.ex:112: anonymous fn/2 in TictactoeWeb.GameLive.check_winner/1
    (elixir 1.18.3) lib/enum.ex:4432: Enum.find_value_list/3
    (tictactoe 0.1.0) lib/tictactoe_web/live/game_live.ex:111: TictactoeWeb.GameLive.check_winner/1
    (tictactoe 0.1.0) lib/tictactoe_web/live/game_live.ex:64: TictactoeWeb.GameLive.handle_event/3
    (phoenix_live_view 1.0.17) lib/phoenix_live_view/channel.ex:509: anonymous fn/3 in Phoenix.LiveView.Channel.view_handle_event/3
    (telemetry 1.3.0) /Users/yamauchi/Documents/13_Elixir/games/tictactoe/deps/telemetry/src/telemetry.erl:324: :telemetry.span/3
    (phoenix_live_view 1.0.17) lib/phoenix_live_view/channel.ex:260: Phoenix.LiveView.Channel.handle_info/2
    (stdlib 6.2.2) gen_server.erl:2345: :gen_server.try_handle_info/3
    (stdlib 6.2.2) gen_server.erl:2433: :gen_server.handle_msg/6
    (stdlib 6.2.2) proc_lib.erl:340: :proc_lib.wake_up/3
Last message: %Phoenix.Socket.Message{topic: "lv:phx-GEl9gRshWKOdcQFm", event: "event", payload: %{"event" => "mark", "type" => "click", "value" => %{"index" => "1", "value" => ""}}, ref: "23", join_ref: "21"}
State: %{socket: #Phoenix.LiveView.Socket<id: "phx-GEl9gRshWKOdcQFm", endpoint: TictactoeWeb.Endpoint, view: TictactoeWeb.GameLive, parent_pid: nil, root_pid: #PID<0.771.0>, router: TictactoeWeb.Router, assigns: %{flash: %{}, __changed__: %{}, board: [nil, nil, nil, nil, nil, nil, nil, nil, nil], current_player: "X", game_over: false, winner: nil, game_state: "playing", live_action: nil}, transport_pid: #PID<0.758.0>, sticky?: false, ...>, components: {%{}, %{}, 1}, topic: "lv:phx-GEl9gRshWKOdcQFm", serializer: Phoenix.Socket.V2.JSONSerializer, join_ref: "21", redirect_count: 0, upload_names: %{}, upload_pids: %{}}
[debug] MOUNT TictactoeWeb.GameLive
  Parameters: %{}
  Session: %{"_csrf_token" => "xhK2ly-vmoIRoXaXrmM-DZUH"}
[debug] Replied in 185µs
[debug] HANDLE EVENT "mark" in TictactoeWeb.GameLive
  Parameters: %{"index" => "8", "value" => ""}
[error] GenServer #PID<0.772.0> terminating
** (ArgumentError) the Access module does not support accessing lists by index, got: 0

Accessing a list by index is typically discouraged in Elixir, instead we prefer to use the Enum module to manipulate lists as a whole. If you really must access a list element by index, you can use Enum.at/2 or the functions in the List module
    (elixir 1.18.3) lib/access.ex:347: Access.get/3
    (tictactoe 0.1.0) lib/tictactoe_web/live/game_live.ex:112: anonymous fn/2 in TictactoeWeb.GameLive.check_winner/1
    (elixir 1.18.3) lib/enum.ex:4432: Enum.find_value_list/3
    (tictactoe 0.1.0) lib/tictactoe_web/live/game_live.ex:111: TictactoeWeb.GameLive.check_winner/1
    (tictactoe 0.1.0) lib/tictactoe_web/live/game_live.ex:64: TictactoeWeb.GameLive.handle_event/3
    (phoenix_live_view 1.0.17) lib/phoenix_live_view/channel.ex:509: anonymous fn/3 in Phoenix.LiveView.Channel.view_handle_event/3
    (telemetry 1.3.0) /Users/yamauchi/Documents/13_Elixir/games/tictactoe/deps/telemetry/src/telemetry.erl:324: :telemetry.span/3
    (phoenix_live_view 1.0.17) lib/phoenix_live_view/channel.ex:260: Phoenix.LiveView.Channel.handle_info/2
    (stdlib 6.2.2) gen_server.erl:2345: :gen_server.try_handle_info/3
    (stdlib 6.2.2) gen_server.erl:2433: :gen_server.handle_msg/6
    (stdlib 6.2.2) proc_lib.erl:329: :proc_lib.init_p_do_apply/3
Last message: %Phoenix.Socket.Message{topic: "lv:phx-GEl9gRshWKOdcQFm", event: "event", payload: %{"event" => "mark", "type" => "click", "value" => %{"index" => "8", "value" => ""}}, ref: "25", join_ref: "24"}
State: %{socket: #Phoenix.LiveView.Socket<id: "phx-GEl9gRshWKOdcQFm", endpoint: TictactoeWeb.Endpoint, view: TictactoeWeb.GameLive, parent_pid: nil, root_pid: #PID<0.772.0>, router: TictactoeWeb.Router, assigns: %{flash: %{}, __changed__: %{}, board: [nil, nil, nil, nil, nil, nil, nil, nil, nil], current_player: "X", game_over: false, winner: nil, game_state: "playing", live_action: nil}, transport_pid: #PID<0.758.0>, sticky?: false, ...>, components: {%{}, %{}, 1}, topic: "lv:phx-GEl9gRshWKOdcQFm", serializer: Phoenix.Socket.V2.JSONSerializer, join_ref: "24", redirect_count: 0, upload_names: %{}, upload_pids: %{}}
[debug] MOUNT TictactoeWeb.GameLive
  Parameters: %{}
  Session: %{"_csrf_token" => "xhK2ly-vmoIRoXaXrmM-DZUH"}
[debug] Replied in 252µs
^C

> 枠を触るとエラーがでます。修正してください。ssing lists by index, got: 0"21"}
State: %{socket: #Phoenix.LiveView.Socket<id: "phx-GEl9gRshWKOdcQFm", endpoint: TictactoeWeb.Endpoint, view: TictactoeWeb.GameLive, parent_pid: nil, root_pid: #PID<0.771.0>, router: TictactoeWeb.Router, assigns: %{flash: %{}, __changed__: %{}, board: [nil, nil, nil, nil, nil, nil, nil, nil, nil], current_player: "X", game_over: false, winner: nil, game_state: "playing", live_action: nil}, transport_pid: #PID<0.758.0>, sticky?: false, ...>, components: {%{}, %{}, 1}, topic: "lv:phx-GEl9gRshWKOdcQFm", sState: %{socket: #Phoenix.LiveView.Socket<id: "phx-GEl9gRshWKOdcQFm", endpoint: TictactoeWeb.Endpoint, view: TictactoeWeb.GameLive, parent_pid: nil, root_pid: #PID<0.771.0>, router: TictactoeWeb.Router, assigns: %{flash: %{}, __changed__: %{}, board: [nil, nil, nil, nil, nil, nil, nil, nil, nil], current_player: "X", game_over: false, winner: nil, game_state: "playing", live_action: nil}, transport_pid: #PID<0.758.0>, sticky?: false, ...>, components: {%{}, %{}, 1}, topic: "lv:p
エラーメッセージから、リストのインデックスアクセスに問題があるようです。Elixirで
はリストのインデックスアクセスに Enum.at/2 を使う必要がありますが、コード内で 
board[a] のような形式でアクセスしているところがエラーの原因です。修正しましょう
。


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  111, 111:     winner = Enum.find_value(winning_combinations, fn [a, b, c] ->
- 112     :       if board[a] && board[a] == board[b] && board[a] == board[c] do
- 113     :         board[a]
+      112:       value_a = Enum.at(board, a)
+      113:       value_b = Enum.at(board, b)
+      114:       value_c = Enum.at(board, c)
+      115:       if value_a && value_a == value_b && value_a == value_c do
+      116:         value_a
  114, 117:       else
  115, 118:         nil
  116, 119:       end
  117, 120:     end)

Updating: tictactoe/lib/tictactoe_web/live/game_live.ex

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問題を修正しました。エラーの原因は、Elixirのリストに対して board[a] のような形式
でアクセスしていたことです。Elixirではリストの要素にアクセスするには Enum.at/2 
関数を使う必要があります。

修正したコードでは:

elixir
value_a = Enum.at(board, a)
value_b = Enum.at(board, b)
value_c = Enum.at(board, c)
if value_a && value_a == value_b && value_a == value_c do
  value_a
else
  nil
end


このように、リストのインデックスアクセスを Enum.at/2 関数を使って行うように変更
しました。これでゲームが正常に動作するはずです。

ブラウザで http://localhost:4000/game にアクセスすると、Tic Tac Toeゲームをプレ
イできます。ゲームの機能は以下の通りです:

• 3x3のグリッドでXとOを交互に配置
• 現在のプレイヤーが表示される
• 勝者が決まるとメッセージが表示される
• 引き分けの場合もメッセージが表示される
• リスタートボタンでゲームをリセット可能

> State: %{socket: #Phoenix.LiveView.Socket<id: "phx-GEl9gRshWKOdcQFm", endpoint: TictactoeWeb.Endpoint, view: TictactoeWeb.GameLive, parent_pid: nil, root_pid: #PID<0.771.0>, router: TictactoeWeb.Router, assigns: %{flash: %{}, __changed__: %{}, board: [nil, nil, nil, nil, nil, nil, nil, nil, nil], current_player: "X", game_over: false, winner: nil, game_state: "playing", live_action: nil}, transport_pid: #PID<0.758.0>, sticky?: false, ...>, components: {%{}, %{}, 1}, topic: "lv:phx-GEl9gRshWKOdcQFm", sState: %{socket: #Phoenix.LiveView.Socket<id: "phx-GEl9gRshWKOdcQFm", endpoint: TictactoeWeb.Endpoint, view: TictactoeWeb.GameLive, parent_pid: nil, root_pid: #PID<0.771.0>, router: TictactoeWeb.Router, assigns: %{flash: %{}, __changed__: %{}, board: [nil, nil, nil, nil, nil, nil, nil, nil, nil], current_player: "X", game_over: false, winner: nil, game_state: "playing", live_action: nil}, transport_pid: #PID<0.758.0>, sticky?: false, ...>, componen
ts: {%{}, %{}, 1}, topic: "lv:phx-GEl9gRshWKOdcQFm", sStatex is ty
申し訳ありませんが、メッセージの最後部分が途切れているようです。

LiveViewのステート情報を確認すると、現在のゲーム状態は以下のようになっています：

• board: [nil, nil, nil, nil, nil, nil, nil, nil, nil] - 空のボード（まだ誰も手
を打っていない）
• current_player: "X" - 現在のプレイヤーはX
• game_over: false - ゲームはまだ終了していない
• winner: nil - 勝者はまだいない
• game_state: "playing" - ゲームは進行中

これはゲームの初期状態で、すべてが正常に動作しているように見えます。ゲームを進め
るには、ボード上のセルをクリックして、交互にXとOを配置していくことができます。

何か特定の問題や質問がありましたら、もう少し詳しく教えていただければと思います。

> Please start game
I'll help you start the Tic Tac Toe game. To start playing the game, you need to
:

1. Make sure the Phoenix server is running (if it's not already running)
2. Access the game in your browser

Let me help you with both steps:


🛠️  Using tool: execute_bash (trusted)
 ⋮ 
 ● I will run the following shell command: 
ps aux | grep "phx.server" | grep -v grep
 ⋮ 
 ↳ Purpose: Check if Phoenix server is running

yamauchi         36714   0.0  0.3 412946896 108528 s003  S+    6:58AM   0:03.81 /Users/yamauchi/.asdf/installs/erlang/27.3.3/erts-15.2.6/bin/beam.smp -- -root /Users/yamauchi/.asdf/installs/erlang/27.3.3 -bindir /Users/yamauchi/.asdf/installs/erlang/27.3.3/erts-15.2.6/bin -progname erl -- -home /Users/yamauchi -- -noshell -elixir_root /Users/yamauchi/.asdf/installs/elixir/1.18.3-otp-27/bin/../lib -pa /Users/yamauchi/.asdf/installs/elixir/1.18.3-otp-27/bin/../lib/elixir/ebin -s elixir start_cli -- -- -extra /Users/yamauchi/.asdf/installs/elixir/1.18.3-otp-27/bin/mix phx.server
yamauchi         36713   0.0  0.0 410725232   1936 s003  S+    6:58AM   0:00.00 bash -c cd tictactoe && mix phx.server

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 ● Completed in 0.118s
Great! I can see that the Phoenix server is already running. Now you can access 
the game in your browser by going to:

http://localhost:4000/game


Open this URL in your web browser, and you'll see the Tic Tac Toe game 
interface. Here's how to play:

1. The game starts with player "X" going first
2. Click on any empty cell to place your mark (X or O)
3. Players take turns until someone wins or the game ends in a draw
4. A player wins by getting three of their marks in a row (horizontally, 
vertically, or diagonally)
5. If all cells are filled and no one has won, the game ends in a draw
6. You can click the "Restart Game" button at any time to start over

The game is already running and ready to play. Enjoy your Tic Tac Toe game!

> 動きました。ありがとう。READMEに遊び方を書き足してください。
READMEに遊び方を追加しましょう。


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🛠️  Using tool: fs_write (trusted)
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   1,  1: # Tictactoe
   2,  2: 
+      3: Phoenix LiveViewで実装した対戦型三目並べ（Tic Tac Toe）ゲームです。
+      4: 
+      5: ## 起動方法
+      6: 
   3,  7: To start your Phoenix server:
   4,  8: 
   5,  9:   * Run `mix setup` to install and setup dependencies
   6, 10:   * Start Phoenix endpoint with `mix phx.server` or inside IEx with `iex -S mix phx.server`
   7, 11: 
-  8    : Now you can visit [`localhost:4000`](http://localhost:4000) from your browser.
+     12: Now you can visit [`localhost:4000/game`](http://localhost:4000/game) from your browser to play the game.
+     13: 
+     14: ## 遊び方
+     15: 
+     16: 1. ゲームは自動的にプレイヤーX（先手）から始まります
+     17: 2. プレイヤーは交互に空いているマス目をクリックして、自分のマーク（XまたはO）を配置します
+     18: 3. 以下のいずれかの条件でゲームが終了します：
+     19:    - いずれかのプレイヤーが横、縦、または斜めに3つ自分のマークを並べた場合（勝利）
+     20:    - すべてのマス目が埋まり、勝者がいない場合（引き分け）
+     21: 4. ゲームが終了すると、結果（勝者または引き分け）が表示されます
+     22: 5. 「Restart Game」ボタンをクリックすると、いつでもゲームをリセットできます
+     23: 
+     24: ## 特徴
+     25: 
+     26: - Phoenix LiveViewを使用したリアルタイム更新
+     27: - データベース不要の軽量設計
+     28: - レスポンシブなUIデザイン
+     29: - 現在のプレイヤー表示
+     30: - ゲーム状態の視覚的フィードバック
   9, 31: 
  10, 32: Ready to run in production? Please [check our deployment guides](https://hexdocs.pm/phoenix/deployment.html).

Updating: tictactoe/README.md

 ⋮ 
 ● Completed in 0.1s
READMEに遊び方を追加しました！以下の内容を追加しています：

1. ゲームの概要（Phoenix LiveViewで実装した三目並べゲーム）
2. 正しいURLの案内（localhost:4000/game）
3. 詳細な遊び方の説明
   • ゲームの開始方法
   • プレイヤーの交代ルール
   • 勝利条件と引き分け条件
   • ゲーム終了時の表示
   • リスタート方法
4. ゲームの特徴
   • Phoenix LiveViewの活用
   • データベース不要の設計
   • レスポンシブUI
   • プレイヤー表示
   • 視覚的フィードバック

これで、初めてゲームをプレイする人でも簡単に理解できるようになりました。ゲームが正常に動作して良かったです！何か他に追
加や変更したい点があれば、お知らせください。

> git initしてcommitしておいて
git initでリポジトリを初期化し、最初のコミットを作成しましょう。


🛠️  Using tool: execute_bash (trusted)
 ⋮ 
 ● I will run the following shell command: 
cd tictactoe && git init
 ⋮ 
 ↳ Purpose: gitリポジトリを初期化

Initialized empty Git repository in /Users/yamauchi/Documents/13_Elixir/games/tictactoe/.git/

 ⋮ 
 ● Completed in 0.46s



🛠️  Using tool: execute_bash (trusted)
 ⋮ 
 ● I will run the following shell command: 
cd tictactoe && git add .
 ⋮ 
 ↳ Purpose: gitにファイルを追加


 ⋮ 
 ● Completed in 0.58s



🛠️  Using tool: execute_bash (trusted)
 ⋮ 
 ● I will run the following shell command: 
cd tictactoe && git commit -m "Initial commit: Phoenix LiveView Tic Tac Toe game implementation"
 ⋮ 
 ↳ Purpose: コミットを作成

[main (root-commit) 6ced923] Initial commit: Phoenix LiveView Tic Tac Toe game implementation
 42 files changed, 2384 insertions(+)
 create mode 100644 .formatter.exs
 create mode 100644 .gitignore
 create mode 100644 README.md
 create mode 100644 assets/css/app.css
 create mode 100644 assets/js/app.js
 create mode 100644 assets/tailwind.config.js
 create mode 100644 assets/vendor/topbar.js
 create mode 100644 config/config.exs
 create mode 100644 config/dev.exs
 create mode 100644 config/prod.exs
 create mode 100644 config/runtime.exs
 create mode 100644 config/test.exs
 create mode 100644 lib/tictactoe.ex
 create mode 100644 lib/tictactoe/application.ex
 create mode 100644 lib/tictactoe/mailer.ex
 create mode 100644 lib/tictactoe_web.ex
 create mode 100644 lib/tictactoe_web/components/core_components.ex
 create mode 100644 lib/tictactoe_web/components/layouts.ex
 create mode 100644 lib/tictactoe_web/components/layouts/app.html.heex
 create mode 100644 lib/tictactoe_web/components/layouts/root.html.heex
 create mode 100644 lib/tictactoe_web/controllers/error_html.ex
 create mode 100644 lib/tictactoe_web/controllers/error_json.ex
 create mode 100644 lib/tictactoe_web/controllers/page_controller.ex
 create mode 100644 lib/tictactoe_web/controllers/page_html.ex
 create mode 100644 lib/tictactoe_web/controllers/page_html/home.html.heex
 create mode 100644 lib/tictactoe_web/endpoint.ex
 create mode 100644 lib/tictactoe_web/gettext.ex
 create mode 100644 lib/tictactoe_web/live/game_live.ex
 create mode 100644 lib/tictactoe_web/router.ex
 create mode 100644 lib/tictactoe_web/telemetry.ex
 create mode 100644 mix.exs
 create mode 100644 mix.lock
 create mode 100644 priv/gettext/en/LC_MESSAGES/errors.po
 create mode 100644 priv/gettext/errors.pot
 create mode 100644 priv/static/favicon.ico
 create mode 100644 priv/static/images/logo.svg
 create mode 100644 priv/static/robots.txt
 create mode 100644 test/support/conn_case.ex
 create mode 100644 test/test_helper.exs
 create mode 100644 test/tictactoe_web/controllers/error_html_test.exs
 create mode 100644 test/tictactoe_web/controllers/error_json_test.exs
 create mode 100644 test/tictactoe_web/controllers/page_controller_test.exs

 ⋮ 
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🛠️  Using tool: execute_bash (trusted)
 ⋮ 
 ● I will run the following shell command: 
cd tictactoe && git status
 ⋮ 
 ↳ Purpose: gitのステータスを確認

On branch main
nothing to commit, working tree clean

 ⋮ 
 ● Completed in 0.27s
Gitリポジトリを初期化し、最初のコミットを作成しました。

1. git init でリポジトリを初期化しました
2. git add . で全てのファイルをステージングエリアに追加しました
3. git commit -m "Initial commit: Phoenix LiveView Tic Tac Toe game implementation" で最初のコミットを作成しました
4. git status で確認したところ、全てのファイルがコミットされ、作業ディレクトリはクリーンな状態です

これで、Phoenix LiveViewで実装したTic Tac Toeゲームのコードがバージョン管理されるようになりました。今後、機能追加や修
正を行う際には、新しいコミットを作成することで変更履歴を追跡できます。

必要に応じて、GitHubなどのリモートリポジトリにプッシュすることもできます。その場合は以下のコマンドを実行します：

bash
git remote add origin <リポジトリのURL>
git push -u origin main
```

</details>


# GitHubに置いたよ

GitHubにソースコードを置いておきます。

https://github.com/TORIFUKUKaiou/tictactoe

# さいごに

Amazon Q CLIさんを使ってTic Tac Toeを実装できました。
 **<b><font color="red">$\huge{T}$</font></b>ic <b><font color="red">$\huge{T}$</font></b>ac <b><font color="red">$\huge{T}$</font></b>oeだけにマジで`t`押しているだけでできがった感じ（猪木寛至）です！！！**


![output.gif](https://qiita-image-store.s3.ap-northeast-1.amazonaws.com/0/131808/fd0eccfc-88af-4839-83a4-a27a4646b9a2.gif)


<blockquote class="twitter-tweet"><p lang="ja" dir="ltr">Amazon Q CLI x Phoenix LiveView × 闘魂：最速でTic Tac Toeを爆誕させた話 <a href="https://t.co/n8LfjltVdt">https://t.co/n8LfjltVdt</a> <a href="https://twitter.com/hashtag/Qiita?src=hash&amp;ref_src=twsrc%5Etfw">#Qiita</a> <a href="https://twitter.com/torifukukaiou?ref_src=twsrc%5Etfw">@torifukukaiou</a>より <a href="https://twitter.com/hashtag/AmazonQCLI?src=hash&amp;ref_src=twsrc%5Etfw">#AmazonQCLI</a></p>&mdash; TORIFUKU Kaiou (@torifukukaiou) <a href="https://twitter.com/torifukukaiou/status/1934742064685867279?ref_src=twsrc%5Etfw">June 16, 2025</a></blockquote> <script async src="https://platform.twitter.com/widgets.js" charset="utf-8"></script>