func main() {
      // Create a new command system
      system := dcmd.NewStandardSystem("[")

      // Add the time of day command to the root container of the system
      system.Root.AddCommand(&CmdTimeOfDay{Format: time.RFC822}, dcmd.NewTrigger("Time", "t"))

      // Create the discordgo session
      session, err := discordgo.New(os.Getenv("DG_TOKEN"))
      if err != nil {
            log.Fatal("Failed setting up session:", err)
      }

      // Add the command system handler to discordgo
      session.AddHandler(system.HandleMessageCreate)

      err = session.Open()
      if err != nil {
            log.Fatal("Failed opening gateway connection:", err)
      }
      log.Println("Running, Ctrl-c to stop.")
      select {}
}

type CmdTimeOfDay struct {
      Format string
}

// Descriptions should return a short description (used in the overall help overiview) and one long descriptions for targetted help
func (t *CmdTimeOfDay) Descriptions(d *dcmd.Data) (string, string) {
      return "Responds with the current time in utc", ""
}

// Run implements the dcmd.Cmd interface and gets called when the command is invoked
func (t *CmdTimeOfDay) Run(data *dcmd.Data) (interface{}, error) {
      return time.Now().UTC().Format(t.Format), nil
}