// reflect2.go package main import ( "fmt" "reflect" ) func main() { var x float64 = 3.4 v := reflect.ValueOf(x) // setting a value: // v.SetFloat(3.1415) // Error: will panic: reflect.Value.SetFloat using unaddressable value fmt.Println("settability of v:", v.CanSet()) v = reflect.ValueOf(&x) // Note: take the address of x. fmt.Println("type of v:", v.Type()) fmt.Println("settability of v:", v.CanSet()) v = v.Elem() fmt.Println("The Elem of v is: ", v) fmt.Println("settability of v:", v.CanSet()) v.SetFloat(3.1415) // this works! fmt.Println(v.Interface()) fmt.Println(v) } /* Output: settability of v: false type of v: *float64 settability of v: false The Elem of v is: settability of v: true 3.1415 */