18 lines
403 B
Forth
18 lines
403 B
Forth
|
module Animals
|
||
|
|
|
||
|
|
// Call a base class from a derived one.
|
||
|
|
type Animal() =
|
||
|
|
member __.Rest() = ()
|
||
|
|
|
||
|
|
type Dog() =
|
||
|
|
inherit Animal()
|
||
|
|
member __.Run() =
|
||
|
|
base.Rest()
|
||
|
|
|
||
|
|
// Upcasting is denoted by :> operator.
|
||
|
|
let dog = Dog()
|
||
|
|
let animal = dog :> Animal
|
||
|
|
|
||
|
|
//Dynamic downcasting (:?>) might throw an InvalidCastException if the cast doesn't succeed at runtime.
|
||
|
|
let shouldBeADog = animal :?> Dog
|