Namespace not found in F# fsx

Question

I've searched around for this but nobody seems to be having quite the same issue with F# .fsx scripts not finding namespaces. I've got Common project that builds fine and is picked up by intellisense in another project but the script in that same project proclaims it as not defined even though hovering over the #r "Common.dll" finds the full path. The common code:

namespace Common
open System
open System.Text
open System.Security.Cryptography

module Guid =
  let swapBytes (a: byte[]) = 
Array.concat [ Array.rev a.[..3] ; Array.rev a.[4..5] ; Array.rev a.[6..7]; a.[8..15] ]

// Implementaion of http://www.ietf.org/rfc/rfc4122.txt section 4.3 version 5 (Name Based using SHA-1)
// Based on C# at https://github.com/LogosBible/Logos.Utility/blob/master/src/Logos.Utility/GuidUtility.cs
type System.Guid with
  static member FromName (guid:System.Guid) (name:string) =
    let nameBytes: byte[] = Encoding.UTF8.GetBytes name
    let nameSpaceBytes = guid.ToByteArray() |> swapBytes

    use algorithm = SHA1.Create()
    algorithm.TransformBlock (nameSpaceBytes, 0, nameSpaceBytes.Length, null, 0) |> ignore
    algorithm.TransformFinalBlock(nameBytes, 0, nameBytes.Length) |> ignore
    let hash = algorithm.Hash;

    let newGuid = Array.create 16 0uy
    Array.Copy(hash, 0, newGuid, 0, 16)

    Array.set newGuid 6 ((newGuid.[6] &&& 0x0Fuy) ||| (5uy <<< 4))
    Array.set newGuid 8 ((newGuid.[8] &&& 0x3Fuy) ||| 0x80uy)

    newGuid |> swapBytes |> System.Guid

The .fsx content:

#I @"..\Common\bin\Debug"
#r "Common.dll"
open Common

let NamedGuid = System.Guid.FromName (Guid("190bbe82-5692-43a4-b825-079f41fc55c0"))

This is in VS2015. What is missing?

Answer 1

You need to open the Guid module as well, or annotate it with the [<AutoOpen>] attribute. This will resolve the reference to System.Guid.FromName .

And after you do that, you will also need to open the System namespace in order to access the Guid constructor (or call System.Guid directly).