Primitive types

func printType(v interface{}) {
	rv := reflect.ValueOf(v)
	typ := rv.Type()
	typeName := ""
	switch rv.Kind() {
	case reflect.Ptr:
		typeName = "pointer"
	case reflect.Int:
		typeName = "int"
	case reflect.Int32:
		typeName = "int32"
	case reflect.String:
		typeName = "string"
	// ... handle more cases
	default:
		typeName = "unrecognized type"
	}
	fmt.Printf("v is of type '%s'. Size: %d bytes\n", typeName, typ.Size())
}

printType(int32(3))
printType("")
i := 3
printType(&i) // *int i.e. pointer to int

func getIntValue(v interface{}) {
	var reflectValue = reflect.ValueOf(v)
	n := reflectValue.Int()
	fmt.Printf("Int value is: %d\n", n)
}

getIntValue(3)
getIntValue(int8(4))
getIntValue("")

type S struct {
	N int
}

func setIntPtr() {
	var n int = 2
	reflect.ValueOf(&n).Elem().SetInt(4)
	fmt.Printf("setIntPtr: n=%d\n", n)
}

func setStructFieldDirect() {
	var s S
	reflect.ValueOf(&s.N).Elem().SetInt(5)
	fmt.Printf("setStructFieldDirect: n=%d\n", s.N)
}

func setStructPtrField() {
	var s S
	reflect.ValueOf(&s).Elem().Field(0).SetInt(6)
	fmt.Printf("setStructPtrField: s.N: %d\n", s.N)
}

func handlePanic(funcName string) {
	if msg := recover(); msg != nil {
		fmt.Printf("%s panicked with '%s'\n", funcName, msg)
	}
}

func setStructField() {
	defer handlePanic("setStructField")
	var s S
	reflect.ValueOf(s).Elem().Field(0).SetInt(4)
	fmt.Printf("s.N: %d\n", s.N)
}

func setInt() {
	defer handlePanic("setInt")
	var n int = 2
	rv := reflect.ValueOf(n)
	rv.Elem().SetInt(4)
}

func setIntPtrWithString() {
	defer handlePanic("setIntPtrWithString")
	var n int = 2
	reflect.ValueOf(&n).Elem().SetString("8")
}