interface Log {
  readonly debug: Reader<string, void>
  readonly error: Reader<string, void>
  readonly info: Reader<string, void>
  readonly log: Reader<string, void>
  readonly warn: Reader<string, void>
}

interface MonadLog {
  readonly debug: MonadFunction<string, void>
  readonly error: MonadFunction<string, void>
  readonly info: MonadFunction<string, void>
  readonly log: MonadFunction<string, void>
  readonly warn: MonadFunction<string, void>
}