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module Interfaces
// You can implement one or more interfaces in a class type by using the interface keyword,
// the name of the interface, and the with keyword, followed by the interface member definitions,
// as shown in the following code.
type IPrintable =
abstract member Print : unit -> unit
abstract member MyReadOnlyProperty :int
type SomeClass1(x: int, y: float) =
interface IPrintable with
member this.Print() = printfn "%d %f" x y
member this.MyReadOnlyProperty = 10
// To call the interface method when you have an object of type SomeClass,
// you must upcast the object to the interface type, as shown in the following code.+
let x1 = new SomeClass1(1, 2.0)
(x1 :> IPrintable).Print()
// An alternative is to declare a method on the object that upcasts and calls the interface method,
// as in the following example.
type SomeClass2(x: int, y: float) =
member this.Print() = (this :> IPrintable).Print()
interface IPrintable with
member this.Print() = printfn "%d %f" x y
member this.MyReadOnlyProperty = 10
let x2 = new SomeClass2(1, 2.0)
x2.Print()
// Interface Inheritance
type Interface0 = interface
abstract member Method1 : int -> int
end
// Interface Inheritance
type Interface1 =
abstract member Method1 : int -> int
type Interface2 =
abstract member Method2 : int -> int
type Interface3 =
inherit Interface1
inherit Interface2
abstract member Method3 : int -> int
type MyClass() =
interface Interface3 with
member this.Method1(n) = 2 * n
member this.Method2(n) = n + 100
member this.Method3(n) = n / 10
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