}

// ExtraUsage implements the plugin.FlagSet interface.
func (f *GoFlags) ExtraUsage() string {
	return strings.Join(f.UsageMsgs, "\n")
}

// AddExtraUsage implements the plugin.FlagSet interface.
func (f *GoFlags) AddExtraUsage(eu string) {
	f.UsageMsgs = append(f.UsageMsgs, eu)
}

// Parse implements the plugin.FlagSet interface.
func (*GoFlags) Parse(usage func()) []string {
	flag.Usage = usage