interface varperror// nil-value of type errorerror.Error()// panic: runtime error: invalid memory address or nil pointer dereference func varffunc(string)// nil-functionf("oh oh")// panic: runtime error: invalid memory address or nil pointer dereference 死锁 nil的channel无法读或者写,会造...
var value int32 func SetValue(delta int32) { for { v := value if atomic.CompareAndSwapInt32(&value, v, (v+delta)) { break } } } 解析: atomic.CompareAndSwapInt32 函数不需要循环调用。 13.下面的程序运行后为什么会爆异常。 type Project struct{} func (p *Project) deferError() { if...
// age := 15 等价于 "var age int" "age = 15" 赋值语句不可以在函数体外 age := 15 fmt.Println("age = ", age) //指定变量的类型,并赋值 var sex string sex = "男" fmt.Println("sex = ", sex) //指定变量类型,但不赋值,使用默认值 var num int fmt.Print("num = ", num) //省...
=nil{return"",err}configReflectType:=reflect.TypeOf(config)fori:=0;i<configReflectType.NumField();i++{structTag:=configReflectType.Field(i).Tag.Get(KeyFieldTag)ifstructTag==env{envConfigReflect:=reflect.ValueOf(config).Field(i).Interface()defauleConfigReflectType:=config.DefaultifenvConfigRe...
3. 退出来, 跟踪Default()是怎么实现slog.Logger的。 代码语言:javascript 复制 vardefaultLogger atomic.Value funcinit(){defaultLogger.Store(New(newDefaultHandler(log.Output)))}// Default returns the default Logger.funcDefault()*Logger{returndefaultLogger.Load().(*Logger)} ...
map的验证中也需要tag关键字dive, 另外,它还有keys和endkeys两tag,验证这2个tag之间map的 key,而不是value值。 validate_map.go Copypackage mainimport("fmt""github.com/go-playground/validator/v10")funcmain(){varmaponemap[string]stringmapone =map[string]string{"one":"jimmmy","two":"tom","thr...
Conn) var variable, value string row := conn.QueryRowContext(context.Background(), "SHOW STATUS WHERE `variable_name` = 'Threads_connected'") row.Scan(&variable, &value) // Display how many connections are opened. // As the connection is closed when the request is deleted, // the ...
func(this *Service)ServeHTTP(w http.ResponseWriter, r *http.Request){varremote *url.URLifstrings.Contains(r.RequestURI,"api/auth") {remote, _ = url.Parse("http://"+ this.auth.host +":"+ this.auth.port)}elseifstrings.Contains(r.RequestURI,"api/us...
VALUE "OriginalFilename", "main.exe" VALUE "ProductName", "VMware Workstation" VALUE "ProductVersion", "17.5.0 build-22583795" END END BLOCK "VarFileInfo" BEGIN VALUE "Translation", 0x0409, 0x04B0 END END 1 ICON "icon1.ico" 编译为 syso 文件 └─# x86_64-w64-mingw32-windres -F ...
import"github.com/ilyakaznacheev/cleanenv"typeConfigDatabasestruct{Portstring`env:"PORT" env-default:"5432"`Hoststring`env:"HOST" env-default:"localhost"`Namestring`env:"NAME" env-default:"postgres"`Userstring`env:"USER" env-default:"user"`Passwordstring`env:"PASSWORD"`}varcfgConfigDatabase...