It also depends on which version of the F # compiler you are using. If you compile your F # code using the F # compiler for .NET 2.0, it will use FSharp.Core.dll for .NET 2.0, which contains the declaration of the Tuple<..> classes. Then you can just reference FSharp.Core.dll to your C # project and you will find tuple there (this is in the System namespace to make it compatible with .NET 4)
I believe that the ZIP version from Microsoft and F # packages contains version 2.0. I'm not sure about the version of F # bundled with Mono 2.10, albeit in Debian.
Tomas petricek
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