title: Children arguments when using :simple_one_for_one strategy
body: <p>When using the <code>:simple_one_for_one</code> strategy, we specify the children to launch dynamically:</p>
  
  <pre><code>supervise([worker(FooServer, [])], strategy: :simple_one_for_one)
  </code></pre>
  
  <p>We then use something like the following to start children:</p>
  
  <pre><code>def start_child(arg1, arg2) do
    Supervisor.start_child(__MODULE__, [arg1, arg2])
  end
  </code></pre>
  
  <p>The <a href="http://elixir-lang.org/docs/stable/elixir/Supervisor.html#start_child/2" rel="nofollow" title="Supervisor Documentation">documentation</a> states (emphasis mine):</p>
  
  <blockquote>
    <p>In the case of :simple_one_for_one, the child specification defined in the supervisor will be used and instead of a child_spec, an arbitrary list of terms is expected. The child process <strong><em>will then be started by appending the given list to the existing function arguments in the child specification</em></strong>.</p>
  </blockquote>
  
  <p>I tried the following</p>
  
  <pre><code>supervise([worker(FooServer, [:foo])], strategy: :simple_one_for_one)
  #                             ^^^^
  #                             "fixed" argument
  </code></pre>
  
  <p>But it seems arguments aren't appended, and I can't find how to access these fixed arguments. Is it even possible to do this?</p>