With Points

Mix.install([
  {:jason, "~> 1.4"},
  {:kino, "~> 0.8.0", override: true},
  {:youtube, github: "brooklinjazz/youtube"},
  {:hidden_cell, github: "brooklinjazz/hidden_cell"}
])

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With Points

You’re going to create a Points module which determines the total score of each team in a generic game after three rounds.

game = %{
  team1_name: "Team Team",
  team2_name: "Exersport",
  round1: %{
    team1: 10,
    team2: 20
  },
  round2: %{
    team1: 30,
    team2: 10
  },
  round3: %{
    team1: 25,
    team2: 30
  }
}

Points.tally(game)
%{"Team Team" => 65, "Exersport" => 60}

Use with to ensure the following:

• If the game provided does not have a :team1_name or team2_name keys return {:error, :invalid}.
• If the game does not have a round1, round2, or round3 key, each with :team1 and :team2 keys return {:error, :invalid}.

Example Solution

defmodule Points do
  def tally(game) do
    with %{team1_name: team1, team2_name: team2} <- game,
         %{round1: %{team1: t1r1, team2: t2r1}} <- game,
         %{round2: %{team1: t1r2, team2: t2r2}} <- game,
         %{round3: %{team1: t1r3, team2: t2r3}} <- game do
      %{}
      |> Map.put(team1, t1r1 + t1r2 + t1r3)
      |> Map.put(team2, t2r1 + t2r2 + t2r3)
    else
      error -> 
        IO.inspect(error)
        {:error, :invalid}
    end
  end
end

Enter your solution below.

defmodule Points do
  @doc """
  Tally points in a generic three round game.

  A valid game will return the teams and their total scores in a map.

      iex> game = %{team1_name: "Team Team", team2_name: "Exersport", round1: %{team1: 10, team2: 20}, round2: %{team1: 30, team2: 10}, round3: %{team1: 25, team2: 30}}
      iex> Points.tally(game)
      %{"Team Team" => 65, "Exersport" => 60}

  The `game` must have a `team1_name` and `team2_name` keys.

      iex> Points.tally(%{no_team_names: true})
      {:error, :invalid}

  The `game` must have a `round1`, `round2`, and `round3` keys.

      iex> Points.tally(%{team1_name: "name1", team2_name: "name2"})
      {:error, :invalid}
  """
  def tally(game) do
    with %{team1_name: team1, team2_name: team2} <- game,
         %{round1: %{team1: t1r1, team2: t2r1}} <- game,
         %{round2: %{team1: t1r2, team2: t2r2}} <- game,
         %{round3: %{team1: t1r3, team2: t2r3}} <- game do
      %{}
      |> Map.put(team1, t1r1 + t1r2 + t1r3)
      |> Map.put(team2, t2r1 + t2r2 + t2r3)
    else
      error ->
        {:error, :invalid}
    end
  end
end

Mark As Completed

file_name = Path.basename(Regex.replace(~r/#.+/, __ENV__.file, ""), ".livemd")

save_name =
  case Path.basename(__DIR__) do
    "reading" -> "with_points_reading"
    "exercises" -> "with_points_exercise"
  end

progress_path = __DIR__ <> "/../progress.json"
existing_progress = File.read!(progress_path) |> Jason.decode!()

default = Map.get(existing_progress, save_name, false)

form =
  Kino.Control.form(
    [
      completed: input = Kino.Input.checkbox("Mark As Completed", default: default)
    ],
    report_changes: true
  )

Task.async(fn ->
  for %{data: %{completed: completed}} <- Kino.Control.stream(form) do
    File.write!(
      progress_path,
      Jason.encode!(Map.put(existing_progress, save_name, completed), pretty: true)
    )
  end
end)

form

Commit Your Progress

Run the following in your command line from the curriculum folder to track and save your progress in a Git commit. Ensure that you do not already have undesired or unrelated changes by running git status or by checking the source control tab in Visual Studio Code.

$ git checkout -b with-points-exercise
$ git add .
$ git commit -m "finish with points exercise"
$ git push origin with-points-exercise

Create a pull request from your with-points-exercise branch to your solutions branch. Please do not create a pull request to the DockYard Academy repository as this will spam our PR tracker.

DockYard Academy Students Only:

Notify your teacher by including @BrooklinJazz in your PR description to get feedback. You (or your teacher) may merge your PR into your solutions branch after review.

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