go学习

package main

import (
    "errors"
    "fmt"
)

//在go语言中的不可思议的事情返局部变量的指针，一切ok

func myfun() *int {
    var a int = 10
    return &a
}

//用来处理常规错误
func myerror() {
    err := errors.New("emit macho dwarf:elf header corrupted")
    if err != nil {
        fmt.Print(err)
    }
}

//还有就是在go中字符串常量可以修改
func main1() {
    var va = float32(3.2)
    var myname = "peter"
    c := []byte(myname)
    c[0] = 'A'
    var rawstring = `hello
    world`
    myname = string(c)
    fmt.Println(*myfun(), myname, rawstring, va)
}

const (
    i = 1
    j = iota
    k
)
const v = iota

func main2() {
    fmt.Print(i, j, k, v)
}

func main() {
    var arr1 [10]int = [10]int{1: 10}
    var arr2 [5]int = [5]int{1: 5}
    //arr2[:] = arr1[:5]
    arr3 := [2]int{1, 2}
    arr4 := [...]int{9, 8, 7, 5}
    arr5 := [...]int{arr2, 1}
    fmt.Print(arr1, "\n", arr2, "\n", arr3, "\n", arr4, "\n", arr5)
}

//go的自定义数据
package main

import (
    "fmt"
)

type person struct {
    name string
    age  int
}

func Older(p1, p2 person) (person, int) {
    if p1.age > p2.age {
        return p1, p1.age - p2.age
    } else {
        return p2, p2.age - p2.age
    }
}
func main() {
    var tom person
    tom.name, tom.age = "lisi", 200
    bob := person{name: "wngwu", age: 23}
    //mary := person{"haha",89}
    ret, diff := Older(tom, bob)
    fmt.Print(ret, diff)
}


//struct匿名字段
package main

import (
    "fmt"
)

type person struct {
    Human
    name string
    age  int
}

type Human struct {
    widgth int
}

func Older(p1, p2 person) (person, int) {
    if p1.age > p2.age {
        return p1, p1.age - p2.age
    } else {
        return p2, p2.age - p2.age
    }
}
func main() {
    var tom person
    tom.Human, tom.name, tom.age = Human{89}, "lisi", 200
    bob := person{name: "wngwu", age: 223}
    bob.Human = Human{899}
    ret, diff := Older(tom, bob)
    fmt.Print(ret, diff)
}