Declaring a object public and then using it locally in F#

Question

I don't know much about F# but i am working on a project (on C#) in which i have to make few changes inside pre-written F# code.

I want to declare a object public and then use this object locally.(like we do in C#).

class abc
{
   public SubscriptionManager subman = null;  // object of class SubscriptionManager

   public void DoSomething()
   {
      subman = new SubscriptionManager();
   }
}

Something like this.

Can i do this same thing into the F#?

You aren't declaring any objects. `subman` is a field of `abc`. You can define classes and fields in F# too. — Panagiotis Kanavos, Feb 08 '17 at 11:21
Can you explain why you want to do this? Mutable public fields are not idiomatic in C#, nevermind F#. If you explain more about the problem, I'm sure there is a better approach. — TheInnerLight, Feb 08 '17 at 11:29

score 5 · Accepted Answer · edited May 23 '17 at 12:24

As people mentioned in the comments, there are a couple of reasons why this may not be the right thing to do. That being said, this code would give you roughly what you are after:

[<AllowNullLiteral>]
type Manager() = class end

type abc() = 
    member val subman: Manager = null with get, set
    member this.DoSomething() = this.subman <- Manager()

I've included a dummy Manager class just to make the thing compile. There's a related discussion about public fields also here, that lists a solution where at least the mutable fields is not public.

Declaring a object public and then using it locally in F#

1 Answers1