gistfile1.ex

defrecord Sample, foo: 0, bar:

defmodule GenServer do
  defmacro from_record(record) do
    Enum.map record.__record__(:fields), fn({name,_}) ->
      quote do
        def handle_call(unquote(name), from, record) do
          apply record, name, []
        end

        def handle_call({ name, value }, from, record) do
          apply record, name, [value]
        end
      end
    end
  end
end

defmodule MyServer do
  @behavior :gen_server
  
  def init(_) do
    { :ok, Sample.new }
  end

  GenServer.from_record(Sample)
  
  # Implement other callbacks
end