var P person  // P現(xiàn)在就是person類型的變量了

P.name = "Astaxie"  // 賦值"Astaxie"給P的name屬性.
P.age = 25  // 賦值"25"給變量P的age屬性
fmt.Printf("The person's name is %s", P.name)  // 訪問P的name屬性.

// 聲明一個(gè)新的類型
type person struct {
    name string
    age int
}

// 比較兩個(gè)人的年齡，返回年齡大的那個(gè)人，并且返回年齡差
// struct也是傳值的
func Older(p1, p2 person) (person, int) {
    if p1.age>p2.age {  // 比較p1和p2這兩個(gè)人的年齡
        return p1, p1.age-p2.age
    }
    return p2, p2.age-p1.age
}

func main() {
    var tom person

    // 賦值初始化
    tom.name, tom.age = "Tom", 18

    // 兩個(gè)字段都寫清楚的初始化
    bob := person{age:25, name:"Bob"}

    // 按照struct定義順序初始化值
    paul := person{"Paul", 43}

    tb_Older, tb_diff := Older(tom, bob)
    tp_Older, tp_diff := Older(tom, paul)
    bp_Older, bp_diff := Older(bob, paul)

    fmt.Printf("Of %s and %s, %s is older by %d years\n",
        tom.name, bob.name, tb_Older.name, tb_diff)

    fmt.Printf("Of %s and %s, %s is older by %d years\n",
        tom.name, paul.name, tp_Older.name, tp_diff)

    fmt.Printf("Of %s and %s, %s is older by %d years\n",
        bob.name, paul.name, bp_Older.name, bp_diff)
}

type Human struct {
    name string
    age int
    weight int
}

type Student struct {
    Human  // 匿名字段，那么默認(rèn)Student就包含了Human的所有字段
    speciality string
}

func main() {
    // 我們初始化一個(gè)學(xué)生
    mark := Student{Human{"Mark", 25, 120}, "Computer Science"}

    // 我們?cè)L問相應(yīng)的字段
    fmt.Println("His name is ", mark.name)
    fmt.Println("His age is ", mark.age)
    fmt.Println("His weight is ", mark.weight)
    fmt.Println("His speciality is ", mark.speciality)
    // 修改對(duì)應(yīng)的備注信息
    mark.speciality = "AI"
    fmt.Println("Mark changed his speciality")
    fmt.Println("His speciality is ", mark.speciality)
    // 修改他的年齡信息
    fmt.Println("Mark become old")
    mark.age = 46
    fmt.Println("His age is", mark.age)
    // 修改他的體重信息
    fmt.Println("Mark is not an athlet anymore")
    mark.weight += 60
    fmt.Println("His weight is", mark.weight)
}

type Skills []string

type Human struct {
    name string
    age int
    weight int
}

type Student struct {
    Human  // 匿名字段，struct
    Skills // 匿名字段，自定義的類型string slice
    int    // 內(nèi)置類型作為匿名字段
    speciality string
}

func main() {
    // 初始化學(xué)生Jane
    jane := Student{Human:Human{"Jane", 35, 100}, speciality:"Biology"}
    // 現(xiàn)在我們來(lái)訪問相應(yīng)的字段
    fmt.Println("Her name is ", jane.name)
    fmt.Println("Her age is ", jane.age)
    fmt.Println("Her weight is ", jane.weight)
    fmt.Println("Her speciality is ", jane.speciality)
    // 我們來(lái)修改他的skill技能字段
    jane.Skills = []string{"anatomy"}
    fmt.Println("Her skills are ", jane.Skills)
    fmt.Println("She acquired two new ones ")
    jane.Skills = append(jane.Skills, "physics", "golang")
    fmt.Println("Her skills now are ", jane.Skills)
    // 修改匿名內(nèi)置類型字段
    jane.int = 3
    fmt.Println("Her preferred number is", jane.int)
}

type Human struct {
    name string
    age int
    phone string  // Human類型擁有的字段
}

type Employee struct {
    Human  // 匿名字段Human
    speciality string
    phone string  // 雇員的phone字段
}

func main() {
    Bob := Employee{Human{"Bob", 34, "777-444-XXXX"}, "Designer", "333-222"}
    fmt.Println("Bob's work phone is:", Bob.phone)
    // 如果我們要訪問Human的phone字段
    fmt.Println("Bob's personal phone is:", Bob.Human.phone)
}