code: func FprintfIfNotEmpty(w io.Writer, format string, v interface{}) {
  	if v != nil && v != "" {
  		fmt.Fprintf(w, format, v)
  	}
  }
docs: // FprintfIfNotEmpty prints only if `s` is not empty.
  //
  // NOTE(stevvooe): Not even remotely a printf function.. doesn't take args.