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Pseudo-attribute: InternalCall
f#

Hi,

I need to convert the following two C# lines into F#:

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  [MethodImplAttribute(MethodImplOptions.InternalCall)]


  extern static int api (int x);

I tried this:

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[MethodImplAttribute(MethodImplOptions.InternalCall)]


extern int api(int x);

It compiles, but I get an exception when I try to call the function :
Unhandled Exception: Microsoft.FSharp.Core.FailureException: extern was not given a DllImport attribute

Is it a bug? An internal call shouldn't need any dll file.

For those wondering, I'm embeding mono in a C++ application. The "api" function is defined in the application, so it's considered as internal.

Thanks.

Laurent.

.

The F# compiler does not handle that particular annotation on a method. Usually the internal call shouldn't be used if not only by the runtime. Being in the same executable is not enough to ensure you are preserving the calling convention of the runtime. Are you sure this is the right thing to do even in C# on Mono? On Rotor would be wrong.

In any case you need a small assembly written in C# with the InternalCall declarations and refer this assembly from F#.

Antonio

By on 12/2/2007 11:11 AM ()

Hi,

This is detailed on this page (so, I guess this is a right thing to do on Mono) : [link:www.mono-project.com]. I'm using the function "mono_add_internal_call" (so, it's really an intercall, for the F# code).

This is not very important, because I have other solutions. I can also use P/Invoke or write these declarations C#.

Laurent.

By on 12/2/2007 12:59 PM ()

Hi Laurent,

Thanks for this bug report - I didn't know you could do that on Mono! We've got the issue flagged.

Kind regards

don

By on 12/2/2007 6:58 PM ()

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