def call(conn, _options) do with user_id when not is_nil(user_id) <- get_session(conn, :user_id), user when not is_nil(user) <- Repo.get(User, user_id) do assign(conn, :current_user, user) else _ -> conn |> Controller.put_flash(:error, "You have to sign in to access this page.") |> Controller.redirect(to: "/sign_in_links/new") |> halt end
end

defmodule SomeModule do require Logger @doc """ iex> SomeModule.do_something("Richard") {:ok, "Message sent!"} iex> SomeModule.do_something("Jian") {:error, "Invalid phone number"} iex> SomeModule.do_something("Erlich") {:error, "Not found"} """ def do_something(name) do with {:ok, phone_number} <- look_up(name), :sent <- send_text(phone_number) do {:ok, "Message sent!"} end end def do_something_and_log_error(name) do with {:ok, phone_number} <- look_up(name), :sent <- send_text(phone_number) do {:ok, "Message sent!"} else {:error, error_msg} = error -> Logger.error(error_msg) error end end defp look_up("Richard"), do: {:ok, "+15629998888"} defp look_up("Jian"), do: {:ok, "+864009999999"} defp look_up(_), do: {:error, "Not found"} defp send_text("+1" <> _phone_number), do: :sent defp send_text(_), do: {:error, "Invalid phone number"}
end