tomtsang

if err != nil {
	fmt.Printf("Program stopping with error %v", err)
	os.Exit(1)
}

tomtsang

if err := file.Chmod(0664); err != nil {
	fmt.Println(err)
	return err
}

tomtsang

if value, ok := readData(); ok {
…
}

tomtsang

switch var1 {
	case val1:
		...
	case val2:
		...
	default:
		...
}

tomtsang

switch {
	case condition1:
		...
	case condition2:
		...
	default:
		...
}

tomtsang

switch initialization {
	case val1:
		...
	case val2:
		...
	default:
		...
}

switch result := calculate(); {

tomtsang

switch i {
	case 0: // 空分支，只有当 i == 0 时才会进入分支
	case 1:
		f() // 当 i == 0 时函数不会被调用
}

switch i {
	case 0: fallthrough
	case 1:
		f() // 当 i == 0 时函数也会被调用

tomtsang

// for 初始化语句; 条件语句; 修饰语句 {}
for i := 0; i < 5; i++ {
  fmt.Printf("This is the %d iteration\n", i)
}

/*
初始化语句
for 条件语句 {
  修饰语句

tomtsang

for ix, val := range coll { }

tomtsang

//6.3 传递变长参数
func typecheck(..,..,values … interface{}) {
	for _, value := range values {
		switch v := value.(type) {
			case int: …
			case float: …
			case string: …
			case bool: …
			default: …
		}