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Question - Partially implemented interfaces
f#

Hi,
I'm quite new to F#. I'm under the impression that it is not possible to partially implement an interface.
I'd like to write something like:

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    type IStatistic =
        abstract Accumulate : int -> unit
        abstract Compute : unit -> float
        
    type StatBase =
        interface IStatistic
            abstract Accumulate : int -> unit
            abstract Compute : unit -> float
        member this.Clone () = (this :> obj).MemberwiseClone()

Is this possible at all?
Thanks a lot!
Mau

.

I am unclear exactly what is desired, but below code is suggestive of one strategy (abstract base class that implements interface and has abstract/virtual members for implementation of interface that can overriden or filled out by subclasses).

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type IStatistic =
    abstract Accumulate : int -> unit
    abstract Compute : unit -> float
    
[<AbstractClass>]
type StatBase =
    member this.Foo() = ()
    abstract AccumulateImpl : int -> unit
    abstract ComputeImpl : unit -> float
    default this.ComputeImpl() = raise <| new System.NotImplementedException()
    interface IStatistic with
        member this.Accumulate x = this.AccumulateImpl x
        member this.Compute() = this.ComputeImpl()
By on 7/30/2009 9:47 AM ()

none,
With the code i posted above, I get 2 compiler errors for the missing implementation of StatBase.Accumulate and StatBase.Compute.

Brian,
Iyour solution is fine, I was wondering if it's possible to have a shorter syntax like in my example.

Cheers :)

By on 9/2/2009 4:57 AM ()

Nevermind, it was enough to add the AbstractClass attribute to my original code. Doh!
The following works fine :-)

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    type IStatistic =
        abstract Accumulate : int -> unit
        abstract Compute : unit -> float
    
    [<AbstractClass>]
    type StatBase =
        interface IStatistic
            abstract Accumulate : int -> unit
            abstract Compute : unit -> float
        member this.Clone () =  (this :> obj).MemberwiseClone()
By on 9/2/2009 6:07 AM ()

I get an error on the MemberwiseClone() function. Other than that, everything seems to compile fine. (if i return this from Clone()) What are you trying to do?

By on 7/30/2009 9:46 AM ()

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