Application.ensure_all_started

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ensure_all_started(app, type \\ :temporary)

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Specs

ensure_all_started(app(), restart_type()) ::
  {:ok, [app()]} | {:error, {app(), term()}}

Ensures the given app and its applications are started.

Same as start/2 but also starts the applications listed under :applications in the .app file in case they were not previously started.