反射
package main
import (
"fmt"
"io"
"os"
"reflect"
)
func main() {
t := reflect.TypeOf(3)
fmt.Println(t.String())
fmt.Println(t.Kind().String())
fmt.Println(t)
fmt.Printf("%T\n", 3)
var w io.Writer = os.Stdout
fmt.Println(reflect.TypeOf(w))
}