What is the use of the type switch construct in programming languages?

The type switch construct in Go is used to determine the actual type of a value in an interface at runtime. This allows executing different actions depending on the type of the variable that implements the interface.

Example usage:

var i interface{} = 10

switch v := i.(type) {
case int:
    fmt.Println("int", v)
case string:
    fmt.Println("string", v)
default:
    fmt.Println("unknown type")
}

Here, i.(type) allows checking what specific type is stored in the interface i, and executing the corresponding block of code.