code_reloader_worker.ex

defmodule CodeReloaderWorker do
  use GenServer
  require Logger

  def start_link do
    GenServer.start_link __MODULE__, [], name: __MODULE__
  end

  def init([]) do
    Logger.debug "#{__MODULE__} starting"
    if Mix.env == :dev do
      Logger.debug "DEV detected. Subscribing to .beam and .ex files for recompilation"
      :fs.subscribe
    end
    {:ok, :state}
  end

  def handle_info({_pid, {:fs, :file_event}, {fullpath, _events}}, state) do
    basename = Path.basename fullpath
    #rootname = Path.rootname basename
    extname = Path.extname basename
    case extname do
      ".ex" ->
        # don't recompile emacs .# backup files
        unless binary_part(basename, 0, 2) == ".#" do
          Logger.debug "Recompiling #{fullpath}"
          IEx.Helpers.recompile
        end
      #".beam" ->
      #  Logger.debug "Reloading #{rootname} #{extname}"
      #  IEx.Helpers.r :"#{rootname}"
      _ ->
        :pass
    end
    {:noreply, state}
  end

end