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User Validation

exercises/user_validation.livemd

User Validation

Mix.install([
  {:jason, "~> 1.4"},
  {:kino, "~> 0.9", override: true},
  {:youtube, github: "brooklinjazz/youtube"},
  {:hidden_cell, github: "brooklinjazz/hidden_cell"}
])

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User Validation

You’re going to use with to create a User module that can validate a list of user structs. Handle :missing_name and :not_a_user errors. Return {:ok, user} if the user is valid.

valid_user = %User{name: "Mohsin"}
invalid_user1 = %User{}
invalid_user2 = "Yusef"

[{:ok, %User{name: "Mohsin"}}, {:error, :missing_name}, {:error, :not_a_user}] =
  User.validate_users([valid_user, invalid_user1, invalid_user2])
defmodule User do
  @moduledoc """
  Send messages between users.
  Returns a string of the message if provided valid input.

  ## Examples

    iex> User.validate_users([%User{name: "valid user"}])
    [{:ok, %User{name: "valid user"}}]

    iex> User.validate_users([%User{name: nil}])
    [{:error, :missing_name}]

    iex> User.validate_users(["invalid user", "invalid user", "invalid user"])
    [{:error, :not_a_user}, {:error, :not_a_user}, {:error, :not_a_user}]
  """
  defstruct [:name]

  def validate_users(users) do
    Enum.map(users, fn user ->
      with %User{name: name} <- user, true <- {:missing_name, is_binary(name)} do
        {:ok, user}
      else
        false ->
          {:error, :missing_name}

        _ ->
          {:e}
          IO.inspect(thing)
          :error
      end
    end)
  end
end

Commit Your Progress

DockYard Academy now recommends you use the latest Release rather than forking or cloning our repository.

Run git status to ensure there are no undesirable changes. Then run the following in your command line from the curriculum folder to commit your progress.

$ git add .
$ git commit -m "finish User Validation exercise"
$ git push

We’re proud to offer our open-source curriculum free of charge for anyone to learn from at their own pace.

We also offer a paid course where you can learn from an instructor alongside a cohort of your peers. We will accept applications for the June-August 2023 cohort soon.

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