message: [scmd] update comment.
diff: @@ -178,15 +178,15 @@ where
  /// default_action executed when no subcommand is provided.
  /// quit_action executed when input quit subcommand at console.
  - /// A and Q's fn signature is same but must use different name.
  - pub fn with_default_action<I, A, Q>(
  + // note: D and Q's fn signature is same but is different type.
  + pub fn with_default_action<I, D, Q>(
  state_initializer: I,
  - default_action: A,
  + default_action: D,
  quit_action: Q,
  ) -> Self
  where
  I: Fn(&GlobalOpt) -> Result<State> + 'static,
  - A: Fn(App, GlobalOpt, State) + 'static,
  + D: Fn(App, GlobalOpt, State) + 'static,
  Q: Fn(App, GlobalOpt, State) + 'static,
  {
  //insert console command
  