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How can I hide methods in F sharp?
f#

I am currently implementing a Spec framework in F sharp and I want to hide the Equals, GetHashCode etc. methods on my `should` type, so that the API is not cluttered with these.

I know in C# it is done by making the class implement an interface like this:

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    using System;
    using System.ComponentModel;

    public interface IFluentInterface
    {
        [EditorBrowsable(EditorBrowsableState.Never)]
        bool Equals(object other);

        [EditorBrowsable(EditorBrowsableState.Never)]
        string ToString();

        [EditorBrowsable(EditorBrowsableState.Never)]
        int GetHashCode();

        [EditorBrowsable(EditorBrowsableState.Never)]
        Type GetType();
    }

I tried doing the same in F sharp: 

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    type IFluentInterface = interface
       
        [<EditorBrowsable(EditorBrowsableState.Never)>]
        abstract Equals : (obj) -> bool

        [<EditorBrowsable(EditorBrowsableState.Never)>]
        abstract ToString: unit -> string

        [<EditorBrowsable(EditorBrowsableState.Never)>]
        abstract GetHashCode: unit -> int

        [<EditorBrowsable(EditorBrowsableState.Never)>]
        abstract GetType : unit -> Type 
    end


Implemented it in my type: 

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        interface IFluentInterface with
            member x.Equals(other) = x.Equals(other)
            member x.ToString()    = x.ToString() 
            member x.GetHashCode() = x.GetHashCode()
            member x.GetType()     = x.GetType()

without success.

I also tried to override the methods in my type and adding the attribute that way, but that didn't do the trick either.

So the question remains, how can I clean up my API ?

.

In F# you can disallow Equals & GetHashCode (and remove them from intellisense) by annotating the type with the NoEquality and NoComparison attributes, as shown below. User-defined methods can also be hidden from the intellisense list via the Obsolete attribute or the CompilerMessage attribute with IsHidden=true. There is no way to hide the System.Object methods GetType and ToString from the F# intellisense.

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[<NoEquality; NoComparison>]
type Foo() =
    member x.Bar() = ()
    member x.Qux() = ()
    [<System.Obsolete>]
    member x.HideMe() = ()
    [<CompilerMessage("A warning message",99999,IsError=false,IsHidden=true)>]
    member x.WarnMe() = ()

let foo = new Foo()
foo.
By on 3/5/2010 9:47 AM ()

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