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forcing static init at object creation
f#csla

I've ran into a problem with the CSLA library under F#. CSLA uses a property access method where members utilize information held in a static member. In F# a property declaration is shown below:

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    static member IdProperty = BusinessBase<Months_ROC>.RegisterProperty<int>(new PropertyInfo<int>("Id"))

    member m.Id with get() = m.ReadProperty(Months_ROC.IdProperty)
                and set(v) = m.LoadProperty(Months_ROC.IdProperty, v)

The problem I'm encountering is CSLA expects the static member to be initialized at object creation. This particular code initializes the static property at use and causes an error from the framework stating the static needs to be initialized at creation.

I tried changing static member to static let and that doesn't work.

Is there any way to take control of when a static member is created so I can get past this issue? Thanks in advance!

.

What error do you get when trying to use static let? It seems like it should be the correct solution.

By on 12/3/2012 6:18 AM ()

The following is how I think it should be and it results in a TypeInitializationException. It doesn't even seem to be able to find the RegisterProperty method during run time:

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type CslaTestObj() =
    inherit BusinessBase<CslaTestObj>()

    static let IdProperty = CslaTestObj.RegisterProperty<int>(new PropertyInfo<int>("Id"));

    member m.Id 
        with get() : int = m.ReadProperty(IdProperty) |> unbox
        and set(v) = m.SetProperty(IdProperty, v)
By on 12/3/2012 9:38 AM ()

I don't see anything wrong with this code. Can you run this through the debugger and retrieve the InnerException? I suspect a CSLA-specific problem, which I don't know the first thing about unfortunately.

By on 12/4/2012 9:26 AM ()

Loic,
Thanks much for your assistance. I loaded up CSLA source (C#) and took a look. Here's the RegisterProperty method.

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protected static PropertyInfo<P> RegisterProperty<P>(PropertyInfo<P> info)
{
    return Core.FieldManager.PropertyInfoManager.RegisterProperty<P>(typeof(T), info);
}

I changed protected to public and the static let in my call worked correctly. How can F# call C# protected functions and not have them be treated as private? I'm sure I'm hardly the first person to run into this. I really would rather not rewrite Rocky Lhotka's C# code. He's alot smarter than me :)

Ed

By on 12/4/2012 10:27 PM ()

Try to create a private static member in the inheriting class, which simply imitates the protected member and then use the new member from your static let (members can access protected, let's cannot).

By on 12/5/2012 2:06 AM ()

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