go语言之进阶篇值语义和引用语义

1、值语义和引用语义

示例:

package main

import "fmt"

type Person struct {
        name string //名字
        sex  byte   //性别, 字符类型
        age  int    //年龄
}

//修改成员变量的值

//接收者为普通变量,非指针,值语义,一份拷贝
func (p Person) SetInfoValue(n string, s byte, a int) {
        p.name = n
        p.sex = s
        p.age = a
        fmt.Println("p = ", p)
        fmt.Printf("SetInfoValue &p = %p\n", &p)
}

//接收者为指针变量,引用传递
func (p *Person) SetInfoPointer(n string, s byte, a int) {
        p.name = n
        p.sex = s
        p.age = a

        fmt.Printf("SetInfoPointer p = %p\n", p)
}

func main() {
        s1 := Person{"go", 'm', 22}
        fmt.Printf("&s1 = %p\n", &s1) //打印地址

        //值语义
        //      s1.SetInfoValue("mike", 'm', 18)
        //      fmt.Println("s1 = ", s1) //打印内容

        //引用语义
        (&s1).SetInfoPointer("mike", 'm', 18)
        fmt.Println("s1 = ", s1) //打印内容
}

#执行结果:

&s1 = 0xc00005a400

SetInfoPointer p = 0xc00005a400

s1 =  {mike 109 18}