### Start Yugo.Client in Elixir Application Supervision Tree

Source: https://github.com/flying-toast/yugo/blob/master/README.md

This snippet demonstrates how to integrate `Yugo.Client` into an Elixir application's supervision tree. It shows the basic setup for starting the client with a given name, IMAP server address, username, and password, ensuring it's managed by the application supervisor.

```elixir
defmodule MyApp.Application do
  use Application

  @impl true
  def start(_type, _args) do
    children = [
      {Yugo.Client,
       name: :example_client,
       server: "imap.example.com",
       username: "me@example.com",
       password: "pa55w0rd"}
    ]

    Supervisor.start_link(children, strategy: :one_for_one)
  end
end
```

--------------------------------

### Subscribe to Filtered Emails with Yugo in Elixir

Source: https://github.com/flying-toast/yugo/blob/master/README.md

This example illustrates how to subscribe to email notifications using `Yugo.subscribe/2` with a custom filter. It defines a filter to match subjects containing 'hello' or 'goodbye' and then shows how to receive and inspect incoming email messages that match the criteria.

```elixir
# filter to only notify us about messages containing "hello" or "goodbye" in the subject:
my_filter =
  Yugo.Filter.all()
  |> Yugo.Filter.subject_matches(~r/(hello|goodbye)/)

# By subscribing, our process will be notified about all future emails that match the filter.
Yugo.subscribe(:example_client, my_filter)

receive do
  {:email, _client, message} ->
    IO.puts("Received an email with subject `#{message.subject}`:")
    IO.inspect(message)
end
```

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