Visual Studio 2015 Compiler Errors in F # .NET Core

If I create a .NET Core ( dotnet new -l f# -t lib

) project and two files .fs

, one of which contains code that depends on a type defined in the other, then I see a real-time compiler "red underline" error in the dependent file, even though the code compiles just fine ...

Organizing the source files in Solution Explorer is not a problem and I have the required section "compile":

defined in project.json

. Again, the code compiles successfully.

Is there a way to provide Visual Studio with a key so I don't write code with fake red marks all over the text?