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Convenience of using classes defined in F# from C# ?
f#classesc#

I have some classes defined in F#, with one class per file (module). The class and the source file (module) have the same name. The first part of a typical class module looks something like this:

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namespace BitImage

module BinaryImage

// Class for storing binary images

[<System.Reflection.DefaultMember("Item")>]

type BinaryImage =

// etc...

When referring to such classes from C# code, I need to explicitly use the static class representing the F# module when qualifying the name class name.

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using BitImage;

namespace Foo

{

    class Bar

    {

        static void Main(string[] args)

        {

            // Note duplication of BinaryImage on next line

            BinaryImage.BinaryImage filtered= ImageFactory();

        }

    }

}

Is there are way to avoid this name duplication? For 'functional' style modules containing lots of free functions, then its no problem, but for the more object-oriented parts of my code, which is where it tends to interface with C# code, this duplication seems overly verbose and ugly.

Thanks,

Rob Smallshire

.

Is there a reason you choose to put the type nested inside the module in the F# code? If you put the type in the namespace, it would do what you want, yes?

By on 10/8/2008 1:57 PM ()

Thank you, you are correct. I guess I've read phrases like "...if the module isn't explicitly named, it gets the name of its source file, with the first letter capitalized" (Foundations of F# p. 111) too often. I generally prefer explicit rather than implicit; I didn't expect that explicitly naming the module would change what was created. Going back and reading more carefully I see that on page 329 it follows up with "If you are defining types that will be used from other .NET languages, then you should place them inside a namespace rather than inside a module." Expert F# (p. 163) says "Declarations in files without a leading module or namespace declaration are placed in a module whose name is derived from the name of the implementation file." which does mention the exception to the rule for namespaces.

Rob

By on 10/10/2008 10:54 AM ()

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