Slice使用的一个问题

package main import ( "fmt" "sync" ) type Data struct { A []int32 B []string } func main() { channel := make(chan Data) data := Data{A: make([]int32, 0, 1), B: make([]string, 0, 1)} fmt.Printf("Before gorountine addr, A: %p\n", data.A) fmt.Printf("Before gorountine addr, B: %p\n", data.B) wg := new(sync.WaitGroup) wg.Add(1) go func() { for d := range channel { fmt.Printf("goroutine addr before append, A: %p\n", d.A) fmt.Printf("goroutine addr before append, B: %p\n", d.B) d.A = append(d.A, 23) d.B = append(d.B, "23") //d.A[0] = 23 //d.B[0] = "23" fmt.Printf("goroutine addr after append, A: %p\n", d.A) fmt.Printf("goroutine addr after append, B: %p\n", d.B) fmt.Println(d) } wg.Done() }() fmt.Printf("Before: %v\n", data) channel <- data close(channel) wg.Wait() fmt.Printf("After gorountine addr, A: %p\n", data.A) fmt.Printf("After gorountine addr, B: %p\n", data.B) fmt.Printf("After: %v\n", data) } 代码见上 输出见下： Before gorountine addr, A: 0xc20800a1dc Before gorountine addr, B: 0xc20800a200 Before: {[] []} goroutine addr before append, A: 0xc20800a1dc goroutine addr before append, B: 0xc20800a200 goroutine addr after append, A: 0xc20800a1dc goroutine addr after append, B: 0xc20800a200 {[23] [23]} After gorountine addr, A: 0xc20800a1dc After gorountine addr, B: 0xc20800a200 After: {[] []} 我的问题是：为什么slice的地址没有变，但是master goroutine里的data数据为空？ 如果我去掉append，改为直接赋值，最后data则不为空 需要注意的是，我在make slice的时候特地设置cap为1