anchor.diff:      ++ "v4.0" 
       ++ "Profile" 
       ++ "Profile47" 
  -
  -let private portable7AssembliesPath = 
  -    referenceAssembliesPath
  -    ++ "Framework" 
  -    ++ ".NETPortable" 
  -    ++ "v4.5" 
  -    ++ "Profile" 
  -    ++ "Profile7" 
   
   let private designTimeAssemblies = 
       AppDomain.CurrentDomain.GetAssemblies()
  
positive.code:         | "FSharp.Core", "4.3.1.0" -> fsharp31AssembliesPath
          | "FSharp.Core", "2.3.5.0" -> fsharp30Portable47AssembliesPath
          | "FSharp.Core", "3.3.1.0" -> fsharp31Portable7AssembliesPath
          | "System.Runtime", "4.0.0.0" -> portable7AssembliesPath
          | _, "4.0.0.0" -> net40AssembliesPath
          | _, "2.0.5.0" -> portable47AssembliesPath
          | _, _ -> null
      if folder = null then 
          null
      else
          let assemblyPath = folder ++ (asmName.Name + ".dll")
          if File.Exists assemblyPath then
  
negative.code:     ++ "v4.0"
      ++ "v4.3.1.0"
  
  let private portable47AssembliesPath = 
      referenceAssembliesPath
      ++ "Framework" 
  