anchor.diff:  
   let getReceiptPath installPath = installPath + ".receipt.toml"
   let writeReceipt (installPath : string) location = async {
  -  System.Console.WriteLine (installPath)
  +  System.Console.WriteLine ("writing receipt: " + installPath)
     let receipt = 
       "[receipt]\n" + 
       "path = \"" + installPath + "\"\n" + 
       match location with 
       | Git git -> 
  -      "type = git\n" +
  +      "type = \"git\"\n" +
         "url = \"" + git.Url + "\"\n" + 
         "revision = \"" + git.Revision + "\"\n"
       | Http http -> 
  -      "type = http\n" +
  +      "type = \"http\"\n" +
         "url = \"" + http.Url + "\"\n" + 
         "sha256 = \"" + (http.Sha256) + "\"\n"
       | GitHub gitHub -> 
  -      "type = github\n" +
  -      "owner = " + gitHub.Package.Owner + "\n" +
  -      "project = " + gitHub.Package.Project + "\n" +
  +      "type = \"github\"\n" +
  +      "owner = \""+ gitHub.Package.Owner + "\"\n" +
  +      "project = \"" + gitHub.Package.Project + "\"\n" +
         "revision = \"" + gitHub.Revision + "\"\n"
     
     let receiptPath = getReceiptPath installPath
  
positive.code: let installPackageSources (context : Tasks.TaskContext) (installPath : string) (location : PackageLocation) = async {
    let downloadManager = context.DownloadManager
    let gitManager = context.GitManager
    System.Console.WriteLine installPath
    let! mismatch = compareReceipt installPath location
    if mismatch 
    then
      match location with 
      | GitHub gitHub -> 
        let gitUrl = PackageLocation.gitHubUrl gitHub.Package
  
negative.code:     | false -> async { return false }
      | true -> async {
        let! receipt = Files.readFile receiptPath
        let toml = Toml.parse receipt
        return 
          match toml with
          | Result.Error _ -> 
            false
          | Result.Ok parsed ->
            let oldReceipt = 
              parsed 
  