Question

I’m trying to use the Seq.generate_using function but unfortunately, I don’t seem to be able to find it. I thought it would be living here:

Microsoft.FSharp.Collections.Seq.generate_using 

But it doesn’t. I am getting the error listed below.

C:\Users\Owner\Documents\Visual Studio 2008\Projects\fsharp1\Program.fs(54,63): error FS0039: The value, constructor, namespace or type ‘generate_using’ is not defined. A construct with this name was found in FSharp.PowerPack.dll, which contains some modules and types that were implicitly referenced in some previous versions of F#. You may need to add an explicit reference to this DLL in order to compile this code.

Answer 1

According to the Sept 2008 CTP Release Notes:

The F# library is split into two components. FSharp.Core.dll: Contains the core F# libraries, which will be stabilized and versioned infrequently. FSharp.PowerPack.dll: Contains additional useful F# libraries and tools which will version more frequently, and allow continued innovation on top of the core F# language and libraries.

Some methods in the Seq module were moved into the FSharp.PowerPack assembly, so you can only get those methods by doing the following:

• If you’re using Visual Studio, open your Solution Explorer, right-click on the project file, choose ‘Add Reference’, and add ‘FSharp.PowerPack.dll’.

• If you’re using a script file or fsi, then type #r 'FSharp.PowerPack';; to load the assembly.

Now you should be able to call Seq.generate_using.