anchor.diff:                        XAttribute(NsNone + "Condition", condition))
       }
   
  -let GenerateProjectContent (package : PackageId) (imports : XElement seq) (choose : XElement) =
  +let GenerateProjectContent (package : PackageId) (imports : XElement seq) (choose : XElement seq) =
       let defineName = PackagePropertyName (package.toString)
       let propCondition = sprintf "'$(%s)' == ''" defineName
       let project = XElement (NsMsBuild + "Project",
  
positive.code:                     match fxWhen with
                      | Some x -> yield x
                      | None -> ()
          }
      if whens.Any() then XElement (NsMsBuild + "Choose", whens)
      else null
      
  let GenerateDependenciesContent (dependencies : PackageId seq) =
      seq {
  
negative.code:     let dependencies = NuGets.GetPackageDependencies xnuspec
  
      let imports = GenerateDependenciesContent dependencies
      let choose = GenerateChooseContent libDir package
      let project = GenerateProjectContent package imports choose
  
      let targetFile = pkgDir |> GetFile "package.targets" 
  