Go Part II: Branch statements, functions

This is a creation in Article, where the information may have evolved or changed.

This is the Go second article in the series, which mainly introduces the various usages of if/else, switch and functions.

Series Finishing:

• Go Part I: Variables, constants, and enumeration types

If you are interested in the Go language itself, you can read my translation of the advantages, disadvantages and repulsive design of the go language.

If/else

// 声明可以先于条件，if 中的声明的变量只在此 if/else 有效if num := 9; num < 0 {    } else if num < 10 {    } else {    }

Switch

// 普通 switchswitch time.Now().Weekday() {    // 可以用逗号写多个值    case time.Saturday, time.Sunday:        fmt.Println("It's the weekend")    default:        fmt.Println("It's the weekday")}// 无表达式额的 switchswitch {    case t.Hour() < 12:        fmt.Println("It's before noon")    default:        fmt.Println("It's after noon")}// 比较类型whatAmI := func(i interface{}) {    switch t := i.(type) {        case bool:            fmt.Println("I'm a bool")        case int:            fmt.Println("I'm a int")        default:            fmt.Printf("Don't know type %T\n", t)        }}whatAmI(true)whatAmI(1)whatAmI("hey")

Cycle

// 经典的循环for n := 0; n <= 5; n++ {    if n % 2 == 0 {        continue    }    fmt.Println(n)}// 只有条件for i <= 3 {    fmt.Println(i)    i = i + 1 }// 死循环for {    fmt.Println("loop")    break}

Actual test

Convert an integer to a binary representation

func convertToBin(v int) string {    result := ""    for ; v > 0; v /= 2 {        result = strconv.Itoa(v % 2) + result    }        return result}

Function

// 闭包函数func apply(op func(int, int) int, a, b int) int {    return op(a, b)}func main() {    result := apply(func(i int, i2 int) int {        return int(math.Pow(float64(i), float64(i2)))    }, 2, 2)    fmt.Println(result)}// 可变参数func sum(num ... int) int {    var result = 0    for _, v := range num {        result = result + v    }    return result}c := sum(1, 2, 3)fmt.Println(c)