reactivity

defmodule Reactivity.Signal.Generic do
  @moduledoc """
  Some functions that work on both derived and source signals.
  """

  require Logger
  
  @doc """
  Adds a child to the given signal.
  """
  def add_child({:signal, _, parent}, {:signal, _, child}) do
    GenServer.call(parent, {:add_child, child})
  end

  @doc """
  Gets the last value generated on a node *synchronously*.
  """
  def last_value({:signal, _, signal}) do
    x = GenServer.call(signal, {:last_value})
   Logger.debug "Last value received: #{inspect x}"  
    {:ok, value} = x
    value
  end
end