Find the type of an object

Use fmt for a string type description

You can use the %T flag in the fmt package to get a Go-syntax representation of the type.

var x interface{} = []int{1, 2, 3} xType := fmt.Sprintf("%T", x) fmt.Println(xType) // "[]int"

(The empty interface denoted by interface{} can hold values of any type.)

A type switch lets you choose between types

Use a type switch to do several type assertions in series.

var x interface{} = 2.3 switch v := x.(type) { case int:	fmt.Println("int:", v) case float64:	fmt.Println("float64:", v) default:	fmt.Println("unknown") } // Output: float64: 2.3

Reflection gives full type information

Use the reflect package if the options above don’t suffice.

var x interface{} = []int{1, 2, 3} xType := reflect.TypeOf(x) xValue := reflect.ValueOf(x) fmt.Println(xType, xValue) // "[]int [1 2 3]"