Golang: cast an interface to a typed variable dynamically

Question

In go, is it possible to cast variables dynamically somehow?

For example, if a simple cast would be:

var intAge  = interfaceAge.(int) 

What if I do not know that age is an int in advance? A simple way of writing it would be

var x = getType() var someTypeAge = interfaceAge(.x) 

Is there a way of achieving something like this? The reflect package gives some ways of determining or casting a type at runtime - but I couldn't find anything like the above mentioned (a generic scheme that would work for all types).

Answer 1

No you can't. Go is a static typed language. The type of a variable is determined at compile time.

If you want to determine dynamically the typeof an interface{} you could use type switching:

var t interface{} t = functionOfSomeType() switch t := t.(type) { default:     fmt.Printf("unexpected type %T", t)       // %T prints whatever type t has case bool:     fmt.Printf("boolean %t\n", t)             // t has type bool case int:     fmt.Printf("integer %d\n", t)             // t has type int case *bool:     fmt.Printf("pointer to boolean %t\n", *t) // t has type *bool case *int:     fmt.Printf("pointer to integer %d\n", *t) // t has type *int }