Yes, this is "by design" and not an error in F #. By default, the project templates that we submit (in Visual Studio 2010) will add the following links:
- mscorlib.dll - things like "string"
- FSharp.Core.dll - All Things F #
- System.dll - things like System.IO
- System.Core.dll - .NET 3.5 add-ons such as HashSet <_>
- System.Numerics.dll - for type F # BigInteger
For any specific libraries, such as ADO.NET, WPF, WCF, etc., you will need to add the necessary assembly references.