Question

Is there an option to call a function by reference?

For example:
if I have a variable x in func1 and I want to send it to func2 so it can change it (without returning its new value etc.)

let func1 =
    let mutable x = 1
    func2 x
    System.Console.WriteLine(x)

let func2 x =
    x <- x + 1

So calling func1 will print “2”..

Is it possible? If so, how?

Thanks.

Answer 1

You can use the & operator and byref keyword.

let func1 =
    …
    func2 (&x)
    …

let func2 (x : int byref) =
    …

See MSDN: Reference cells (F#) for more information.