Back to Questions
786
views2
comments
nulls escapes?
f#

I thought in F# null pointers do not escape from the initialization phase,
but the following code raises a null exception after "hi" is printed
(so null escapes). What is wrong with me? 

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15

 
let k f = f ();;

type A(i: int) =
     new() = A(0)
     member this.i = i

let rec x : A =
    k (fun () -> y)
and y : A = 
    k (fun () -> x);;

printfn "%s" "hi";;

x.i;;

Thanks,
Keiko

.

I think this is a compiler bug that is being fixed in SP1 (if I tried it with the right bits at work, I believe it will be raising an InvalidOperationException instead as a result of the recursive-initialization error).

(Regardless, fix the code :) )

By on 1/15/2011 11:25 AM ()

Sadly, as I am using F# on Ubuntu with MonoDevelop plugin, I cannot check it myself with SP1.
But it is nice to know this is a bug and has been fixed; thanks for the reply.

Keiko

By on 1/16/2011 9:11 AM ()

    Topic tags

    IntelliFactory Offices Copyright (c) 2011-2012 IntelliFactory. All rights reserved.
    Home | Products | Consulting | Trainings | Blogs | Jobs | Contact Us | Terms of Use | Privacy Policy | Cookie Policy     		Built with WebSharper