iota 常量自动生成器,每隔1行自动加1

func main() {
	const (
		a = iota
		b
		c
	)
	fmt.Println(a, b, c)
	// 结果为1,2,3
}

同一行,值一样

func main() {
	const (
		a = iota
		b1, b2, b3 = iota, iota, iota
		c = iota
	)
	fmt.Println(a, b1, b2, b3, c)
	// 结果0,1,1,1,2
}