go函数值传递

func testarr(a []int) {
    a = []int{1}
}
func testint(a int) {
    a = 1
}


func testarrptr(a *[]int) {
    b := []int{1}
    a = &b
}
func testintptr(a *int) {
    b := 1
    a = &b
}


func testarrptrval(a *[]int) {
    b := []int{1}
    *a = b
}
func testintptrval(a *int) {
    b := 1
    *a = b
}


func main() {
    var a []int
    b := 0
    testarr(a)
    testint(b)
    fmt.Println("a:", a)
    fmt.Println("b:", b)


    testarrptr(&a)
    testintptr(&b)
    fmt.Println("a:", a)
    fmt.Println("b:", b)


    testarrptrval(&a)
    testintptrval(&b)
    fmt.Println("a:", a)
    fmt.Println("b:", b)
}

输出结果：

a: []
b: 0
a: []
b: 0
a: [1]
b: 1