X3m.System.Test.Router.first

You're seeing just the function first, go back to X3m.System.Test.Router module for more information.

Specs

first(X3m.System.Message.t()) :: :ok

Accepts first service call, routing it's message to Elixir.X3m.System.Test.Controller.first/1.

If result of that invocation is {:reply, %X3m.System.Message{}}, it sends message to message.reply_to pid.

If result of invocation is :noreply, nothing is sent to that pid.

In any case function returns :ok.

Example:

iex> :first |>
...>   X3m.System.Message.new() |>
...>   Elixir.X3m.System.Test.Router.first()
:ok