碰到一个switch case疑惑

我有一个判空函数 ``` func IsEmpty(val interface{}) bool { if val != nil { switch v := val.(type) { case bool: return false case string: return v == "" case int64, int8, int32, int, int16, float64, float32, uint64, uint8, uint32, uint, uint16: return v == 0 case time.Time: return v.IsZero() case []interface{}: return len(v) == 0 case []byte: return len(v) == 0 case []int64: return len(v) == 0 .... } } return true } ``` case数组类型时，觉得代码很恶心 于是我像下面这样写 ``` func IsEmpty(val interface{}) bool { if val != nil { switch v := val.(type) { case bool: return false case string: return v == "" case int64, int8, int32, int, int16, float64, float32, uint64, uint8, uint32, uint, uint16: return v == 0 case time.Time: return v.IsZero() case []interface{}, []byte, []int64....: return len(v) == 0 } } return true } ``` 但是代码报错了，len() 参数错误。 这个地方比较疑惑，求大佬解释一下，或者有什么更好的实现